Imported WebKit commit 2ea9d364d0f6efa8fa64acf19f451504c59be0e4 (http://svn.webkit.org/repository/webkit/trunk@104285)

1 files changed, 2756 insertions, 0 deletions

diff --git a/Source/WebCore/rendering/RenderBlockLineLayout.cpp b/Source/WebCore/rendering/RenderBlockLineLayout.cpp
new file mode 100755
index 000000000..92dceb104
--- /dev/null
+++ b/Source/WebCore/rendering/RenderBlockLineLayout.cpp
@@ -0,0 +1,2756 @@
+/*
+ * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
+ * Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All right reserved.
+ * Copyright (C) 2010 Google Inc. All rights reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public License
+ * along with this library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include "config.h"
+
+#include "BidiResolver.h"
+#include "Hyphenation.h"
+#include "InlineIterator.h"
+#include "InlineTextBox.h"
+#include "Logging.h"
+#include "RenderArena.h"
+#include "RenderCombineText.h"
+#include "RenderFlowThread.h"
+#include "RenderInline.h"
+#include "RenderLayer.h"
+#include "RenderListMarker.h"
+#include "RenderRubyRun.h"
+#include "RenderView.h"
+#include "Settings.h"
+#include "TextBreakIterator.h"
+#include "TrailingFloatsRootInlineBox.h"
+#include "VerticalPositionCache.h"
+#include "break_lines.h"
+#include <wtf/AlwaysInline.h>
+#include <wtf/RefCountedLeakCounter.h>
+#include <wtf/StdLibExtras.h>
+#include <wtf/Vector.h>
+#include <wtf/unicode/CharacterNames.h>
+
+#if ENABLE(SVG)
+#include "RenderSVGInlineText.h"
+#include "SVGRootInlineBox.h"
+#endif
+
+using namespace std;
+using namespace WTF;
+using namespace Unicode;
+
+namespace WebCore {
+
+// We don't let our line box tree for a single line get any deeper than this.
+const unsigned cMaxLineDepth = 200;
+
+class LineWidth {
+public:
+    LineWidth(RenderBlock* block, bool isFirstLine)
+        : m_block(block)
+        , m_uncommittedWidth(0)
+        , m_committedWidth(0)
+        , m_overhangWidth(0)
+        , m_left(0)
+        , m_right(0)
+        , m_availableWidth(0)
+        , m_isFirstLine(isFirstLine)
+    {
+        ASSERT(block);
+        updateAvailableWidth();
+    }
+    bool fitsOnLine() const { return currentWidth() <= m_availableWidth; }
+    bool fitsOnLine(float extra) const { return currentWidth() + extra <= m_availableWidth; }
+    float currentWidth() const { return m_committedWidth + m_uncommittedWidth; }
+
+    // FIXME: We should eventually replace these three functions by ones that work on a higher abstraction.
+    float uncommittedWidth() const { return m_uncommittedWidth; }
+    float committedWidth() const { return m_committedWidth; }
+    float availableWidth() const { return m_availableWidth; }
+
+    void updateAvailableWidth();
+    void shrinkAvailableWidthForNewFloatIfNeeded(RenderBlock::FloatingObject*);
+    void addUncommittedWidth(float delta) { m_uncommittedWidth += delta; }
+    void commit()
+    {
+        m_committedWidth += m_uncommittedWidth;
+        m_uncommittedWidth = 0;
+    }
+    void applyOverhang(RenderRubyRun*, RenderObject* startRenderer, RenderObject* endRenderer);
+    void fitBelowFloats();
+
+private:
+    void computeAvailableWidthFromLeftAndRight()
+    {
+        m_availableWidth = max(0, m_right - m_left) + m_overhangWidth;
+    }
+
+private:
+    RenderBlock* m_block;
+    float m_uncommittedWidth;
+    float m_committedWidth;
+    float m_overhangWidth; // The amount by which |m_availableWidth| has been inflated to account for possible contraction due to ruby overhang.
+    int m_left;
+    int m_right;
+    float m_availableWidth;
+    bool m_isFirstLine;
+};
+
+inline void LineWidth::updateAvailableWidth()
+{
+    int height = m_block->logicalHeight();
+    m_left = m_block->logicalLeftOffsetForLine(height, m_isFirstLine);
+    m_right = m_block->logicalRightOffsetForLine(height, m_isFirstLine);
+
+    computeAvailableWidthFromLeftAndRight();
+}
+
+inline void LineWidth::shrinkAvailableWidthForNewFloatIfNeeded(RenderBlock::FloatingObject* newFloat)
+{
+    int height = m_block->logicalHeight();
+    if (height < m_block->logicalTopForFloat(newFloat) || height >= m_block->logicalBottomForFloat(newFloat))
+        return;
+
+    if (newFloat->type() == RenderBlock::FloatingObject::FloatLeft) {
+        m_left = m_block->logicalRightForFloat(newFloat);
+        if (m_isFirstLine && m_block->style()->isLeftToRightDirection())
+            m_left += m_block->textIndentOffset();
+    } else {
+        m_right = m_block->logicalLeftForFloat(newFloat);
+        if (m_isFirstLine && !m_block->style()->isLeftToRightDirection())
+            m_right -= m_block->textIndentOffset();
+    }
+
+    computeAvailableWidthFromLeftAndRight();
+}
+
+void LineWidth::applyOverhang(RenderRubyRun* rubyRun, RenderObject* startRenderer, RenderObject* endRenderer)
+{
+    int startOverhang;
+    int endOverhang;
+    rubyRun->getOverhang(m_isFirstLine, startRenderer, endRenderer, startOverhang, endOverhang);
+
+    startOverhang = min<int>(startOverhang, m_committedWidth);
+    m_availableWidth += startOverhang;
+
+    endOverhang = max(min<int>(endOverhang, m_availableWidth - currentWidth()), 0);
+    m_availableWidth += endOverhang;
+    m_overhangWidth += startOverhang + endOverhang;
+}
+
+void LineWidth::fitBelowFloats()
+{
+    ASSERT(!m_committedWidth);
+    ASSERT(!fitsOnLine());
+
+    int floatLogicalBottom;
+    int lastFloatLogicalBottom = m_block->logicalHeight();
+    float newLineWidth = m_availableWidth;
+    float newLineLeft = m_left;
+    float newLineRight = m_right;
+    while (true) {
+        floatLogicalBottom = m_block->nextFloatLogicalBottomBelow(lastFloatLogicalBottom);
+        if (floatLogicalBottom <= lastFloatLogicalBottom)
+            break;
+
+        newLineLeft = m_block->logicalLeftOffsetForLine(floatLogicalBottom, m_isFirstLine);
+        newLineRight = m_block->logicalRightOffsetForLine(floatLogicalBottom, m_isFirstLine);
+        newLineWidth = max(0.0f, newLineRight - newLineLeft);
+        lastFloatLogicalBottom = floatLogicalBottom;
+        if (newLineWidth >= m_uncommittedWidth)
+            break;
+    }
+
+    if (newLineWidth > m_availableWidth) {
+        m_block->setLogicalHeight(lastFloatLogicalBottom);
+        m_availableWidth = newLineWidth + m_overhangWidth;
+        m_left = newLineLeft;
+        m_right = newLineRight;
+    }
+}
+
+class LineInfo {
+public:
+    LineInfo()
+        : m_isFirstLine(true)
+        , m_isLastLine(false)
+        , m_isEmpty(true)
+        , m_previousLineBrokeCleanly(true)
+        , m_floatPaginationStrut(0)
+        , m_runsFromLeadingWhitespace(0)
+    { }
+
+    bool isFirstLine() const { return m_isFirstLine; }
+    bool isLastLine() const { return m_isLastLine; }
+    bool isEmpty() const { return m_isEmpty; }
+    bool previousLineBrokeCleanly() const { return m_previousLineBrokeCleanly; }
+    LayoutUnit floatPaginationStrut() const { return m_floatPaginationStrut; }
+    unsigned runsFromLeadingWhitespace() const { return m_runsFromLeadingWhitespace; }
+    void resetRunsFromLeadingWhitespace() { m_runsFromLeadingWhitespace = 0; }
+    void incrementRunsFromLeadingWhitespace() { m_runsFromLeadingWhitespace++; }
+
+    void setFirstLine(bool firstLine) { m_isFirstLine = firstLine; }
+    void setLastLine(bool lastLine) { m_isLastLine = lastLine; }
+    void setEmpty(bool empty, RenderBlock* block = 0, LineWidth* lineWidth = 0)
+    {
+        if (m_isEmpty == empty)
+            return;
+        m_isEmpty = empty;
+        if (!empty && block && floatPaginationStrut()) {
+            block->setLogicalHeight(block->logicalHeight() + floatPaginationStrut());
+            setFloatPaginationStrut(0);
+            lineWidth->updateAvailableWidth();
+        }
+    }
+
+    void setPreviousLineBrokeCleanly(bool previousLineBrokeCleanly) { m_previousLineBrokeCleanly = previousLineBrokeCleanly; }
+    void setFloatPaginationStrut(LayoutUnit strut) { m_floatPaginationStrut = strut; }
+
+private:
+    bool m_isFirstLine;
+    bool m_isLastLine;
+    bool m_isEmpty;
+    bool m_previousLineBrokeCleanly;
+    LayoutUnit m_floatPaginationStrut;
+    unsigned m_runsFromLeadingWhitespace;
+};
+
+static inline LayoutUnit borderPaddingMarginStart(RenderInline* child)
+{
+    return child->marginStart() + child->paddingStart() + child->borderStart();
+}
+
+static inline LayoutUnit borderPaddingMarginEnd(RenderInline* child)
+{
+    return child->marginEnd() + child->paddingEnd() + child->borderEnd();
+}
+
+static LayoutUnit inlineLogicalWidth(RenderObject* child, bool start = true, bool end = true)
+{
+    unsigned lineDepth = 1;
+    LayoutUnit extraWidth = 0;
+    RenderObject* parent = child->parent();
+    while (parent->isRenderInline() && lineDepth++ < cMaxLineDepth) {
+        RenderInline* parentAsRenderInline = toRenderInline(parent);
+        if (start && !child->previousSibling())
+            extraWidth += borderPaddingMarginStart(parentAsRenderInline);
+        if (end && !child->nextSibling())
+            extraWidth += borderPaddingMarginEnd(parentAsRenderInline);
+        child = parent;
+        parent = child->parent();
+    }
+    return extraWidth;
+}
+
+static void determineParagraphDirection(TextDirection& dir, InlineIterator iter)
+{
+    while (!iter.atEnd()) {
+        if (iter.atParagraphSeparator())
+            return;
+        if (UChar current = iter.current()) {
+            Direction charDirection = direction(current);
+            if (charDirection == LeftToRight) {
+                dir = LTR;
+                return;
+            }
+            if (charDirection == RightToLeft || charDirection == RightToLeftArabic) {
+                dir = RTL;
+                return;
+            }
+        }
+        iter.increment();
+    }
+}
+
+static void checkMidpoints(LineMidpointState& lineMidpointState, InlineIterator& lBreak)
+{
+    // Check to see if our last midpoint is a start point beyond the line break.  If so,
+    // shave it off the list, and shave off a trailing space if the previous end point doesn't
+    // preserve whitespace.
+    if (lBreak.m_obj && lineMidpointState.numMidpoints && !(lineMidpointState.numMidpoints % 2)) {
+        InlineIterator* midpoints = lineMidpointState.midpoints.data();
+        InlineIterator& endpoint = midpoints[lineMidpointState.numMidpoints - 2];
+        const InlineIterator& startpoint = midpoints[lineMidpointState.numMidpoints - 1];
+        InlineIterator currpoint = endpoint;
+        while (!currpoint.atEnd() && currpoint != startpoint && currpoint != lBreak)
+            currpoint.increment();
+        if (currpoint == lBreak) {
+            // We hit the line break before the start point.  Shave off the start point.
+            lineMidpointState.numMidpoints--;
+            if (endpoint.m_obj->style()->collapseWhiteSpace())
+                endpoint.m_pos--;
+        }
+    }
+}
+
+static void addMidpoint(LineMidpointState& lineMidpointState, const InlineIterator& midpoint)
+{
+    if (lineMidpointState.midpoints.size() <= lineMidpointState.numMidpoints)
+        lineMidpointState.midpoints.grow(lineMidpointState.numMidpoints + 10);
+
+    InlineIterator* midpoints = lineMidpointState.midpoints.data();
+    midpoints[lineMidpointState.numMidpoints++] = midpoint;
+}
+
+static inline BidiRun* createRun(int start, int end, RenderObject* obj, InlineBidiResolver& resolver)
+{
+    return new (obj->renderArena()) BidiRun(start, end, obj, resolver.context(), resolver.dir());
+}
+
+void RenderBlock::appendRunsForObject(BidiRunList<BidiRun>& runs, int start, int end, RenderObject* obj, InlineBidiResolver& resolver)
+{
+    if (start > end || obj->isFloating() ||
+        (obj->isPositioned() && !obj->style()->isOriginalDisplayInlineType() && !obj->container()->isRenderInline()))
+        return;
+
+    LineMidpointState& lineMidpointState = resolver.midpointState();
+    bool haveNextMidpoint = (lineMidpointState.currentMidpoint < lineMidpointState.numMidpoints);
+    InlineIterator nextMidpoint;
+    if (haveNextMidpoint)
+        nextMidpoint = lineMidpointState.midpoints[lineMidpointState.currentMidpoint];
+    if (lineMidpointState.betweenMidpoints) {
+        if (!(haveNextMidpoint && nextMidpoint.m_obj == obj))
+            return;
+        // This is a new start point. Stop ignoring objects and
+        // adjust our start.
+        lineMidpointState.betweenMidpoints = false;
+        start = nextMidpoint.m_pos;
+        lineMidpointState.currentMidpoint++;
+        if (start < end)
+            return appendRunsForObject(runs, start, end, obj, resolver);
+    } else {
+        if (!haveNextMidpoint || (obj != nextMidpoint.m_obj)) {
+            runs.addRun(createRun(start, end, obj, resolver));
+            return;
+        }
+
+        // An end midpoint has been encountered within our object.  We
+        // need to go ahead and append a run with our endpoint.
+        if (static_cast<int>(nextMidpoint.m_pos + 1) <= end) {
+            lineMidpointState.betweenMidpoints = true;
+            lineMidpointState.currentMidpoint++;
+            if (nextMidpoint.m_pos != UINT_MAX) { // UINT_MAX means stop at the object and don't include any of it.
+                if (static_cast<int>(nextMidpoint.m_pos + 1) > start)
+                    runs.addRun(createRun(start, nextMidpoint.m_pos + 1, obj, resolver));
+                return appendRunsForObject(runs, nextMidpoint.m_pos + 1, end, obj, resolver);
+            }
+        } else
+           runs.addRun(createRun(start, end, obj, resolver));
+    }
+}
+
+static inline InlineBox* createInlineBoxForRenderer(RenderObject* obj, bool isRootLineBox, bool isOnlyRun = false)
+{
+    if (isRootLineBox)
+        return toRenderBlock(obj)->createAndAppendRootInlineBox();
+
+    if (obj->isText()) {
+        InlineTextBox* textBox = toRenderText(obj)->createInlineTextBox();
+        // We only treat a box as text for a <br> if we are on a line by ourself or in strict mode
+        // (Note the use of strict mode.  In "almost strict" mode, we don't treat the box for <br> as text.)
+        if (obj->isBR())
+            textBox->setIsText(isOnlyRun || obj->document()->inNoQuirksMode());
+        return textBox;
+    }
+
+    if (obj->isBox())
+        return toRenderBox(obj)->createInlineBox();
+
+    return toRenderInline(obj)->createAndAppendInlineFlowBox();
+}
+
+static inline void dirtyLineBoxesForRenderer(RenderObject* o, bool fullLayout)
+{
+    if (o->isText()) {
+        if (o->preferredLogicalWidthsDirty() && (o->isCounter() || o->isQuote()))
+            toRenderText(o)->computePreferredLogicalWidths(0); // FIXME: Counters depend on this hack. No clue why. Should be investigated and removed.
+        toRenderText(o)->dirtyLineBoxes(fullLayout);
+    } else
+        toRenderInline(o)->dirtyLineBoxes(fullLayout);
+}
+
+static bool parentIsConstructedOrHaveNext(InlineFlowBox* parentBox)
+{
+    do {
+        if (parentBox->isConstructed() || parentBox->nextOnLine())
+            return true;
+        parentBox = parentBox->parent();
+    } while (parentBox);
+    return false;
+}
+
+InlineFlowBox* RenderBlock::createLineBoxes(RenderObject* obj, const LineInfo& lineInfo, InlineBox* childBox)
+{
+    // See if we have an unconstructed line box for this object that is also
+    // the last item on the line.
+    unsigned lineDepth = 1;
+    InlineFlowBox* parentBox = 0;
+    InlineFlowBox* result = 0;
+    bool hasDefaultLineBoxContain = style()->lineBoxContain() == RenderStyle::initialLineBoxContain();
+    do {
+        ASSERT(obj->isRenderInline() || obj == this);
+
+        RenderInline* inlineFlow = (obj != this) ? toRenderInline(obj) : 0;
+
+        // Get the last box we made for this render object.
+        parentBox = inlineFlow ? inlineFlow->lastLineBox() : toRenderBlock(obj)->lastLineBox();
+
+        // If this box or its ancestor is constructed then it is from a previous line, and we need
+        // to make a new box for our line.  If this box or its ancestor is unconstructed but it has
+        // something following it on the line, then we know we have to make a new box
+        // as well.  In this situation our inline has actually been split in two on
+        // the same line (this can happen with very fancy language mixtures).
+        bool constructedNewBox = false;
+        bool allowedToConstructNewBox = !hasDefaultLineBoxContain || !inlineFlow || inlineFlow->alwaysCreateLineBoxes();
+        bool canUseExistingParentBox = parentBox && !parentIsConstructedOrHaveNext(parentBox);
+        if (allowedToConstructNewBox && !canUseExistingParentBox) {
+            // We need to make a new box for this render object.  Once
+            // made, we need to place it at the end of the current line.
+            InlineBox* newBox = createInlineBoxForRenderer(obj, obj == this);
+            ASSERT(newBox->isInlineFlowBox());
+            parentBox = toInlineFlowBox(newBox);
+            parentBox->setFirstLineStyleBit(lineInfo.isFirstLine());
+            parentBox->setIsHorizontal(isHorizontalWritingMode());
+            if (!hasDefaultLineBoxContain)
+                parentBox->clearDescendantsHaveSameLineHeightAndBaseline();
+            constructedNewBox = true;
+        }
+
+        if (constructedNewBox || canUseExistingParentBox) {
+            if (!result)
+                result = parentBox;
+
+            // If we have hit the block itself, then |box| represents the root
+            // inline box for the line, and it doesn't have to be appended to any parent
+            // inline.
+            if (childBox)
+                parentBox->addToLine(childBox);
+
+            if (!constructedNewBox || obj == this)
+                break;
+
+            childBox = parentBox;
+        }
+
+        // If we've exceeded our line depth, then jump straight to the root and skip all the remaining
+        // intermediate inline flows.
+        obj = (++lineDepth >= cMaxLineDepth) ? this : obj->parent();
+
+    } while (true);
+
+    return result;
+}
+
+static bool reachedEndOfTextRenderer(const BidiRunList<BidiRun>& bidiRuns)
+{
+    BidiRun* run = bidiRuns.logicallyLastRun();
+    if (!run)
+        return true;
+    unsigned int pos = run->stop();
+    RenderObject* r = run->m_object;
+    if (!r->isText() || r->isBR())
+        return false;
+    RenderText* renderText = toRenderText(r);
+    if (pos >= renderText->textLength())
+        return true;
+
+    while (isASCIISpace(renderText->characters()[pos])) {
+        pos++;
+        if (pos >= renderText->textLength())
+            return true;
+    }
+    return false;
+}
+
+RootInlineBox* RenderBlock::constructLine(BidiRunList<BidiRun>& bidiRuns, const LineInfo& lineInfo)
+{
+    ASSERT(bidiRuns.firstRun());
+
+    bool rootHasSelectedChildren = false;
+    InlineFlowBox* parentBox = 0;
+    int runCount = bidiRuns.runCount() - lineInfo.runsFromLeadingWhitespace();
+    for (BidiRun* r = bidiRuns.firstRun(); r; r = r->next()) {
+        // Create a box for our object.
+        bool isOnlyRun = (runCount == 1);
+        if (runCount == 2 && !r->m_object->isListMarker())
+            isOnlyRun = (!style()->isLeftToRightDirection() ? bidiRuns.lastRun() : bidiRuns.firstRun())->m_object->isListMarker();
+
+        InlineBox* box = createInlineBoxForRenderer(r->m_object, false, isOnlyRun);
+        r->m_box = box;
+
+        ASSERT(box);
+        if (!box)
+            continue;
+
+        if (!rootHasSelectedChildren && box->renderer()->selectionState() != RenderObject::SelectionNone)
+            rootHasSelectedChildren = true;
+
+        // If we have no parent box yet, or if the run is not simply a sibling,
+        // then we need to construct inline boxes as necessary to properly enclose the
+        // run's inline box.
+        if (!parentBox || parentBox->renderer() != r->m_object->parent())
+            // Create new inline boxes all the way back to the appropriate insertion point.
+            parentBox = createLineBoxes(r->m_object->parent(), lineInfo, box);
+        else {
+            // Append the inline box to this line.
+            parentBox->addToLine(box);
+        }
+
+        bool visuallyOrdered = r->m_object->style()->rtlOrdering() == VisualOrder;
+        box->setBidiLevel(r->level());
+
+        if (box->isInlineTextBox()) {
+            InlineTextBox* text = toInlineTextBox(box);
+            text->setStart(r->m_start);
+            text->setLen(r->m_stop - r->m_start);
+            text->m_dirOverride = r->dirOverride(visuallyOrdered);
+            if (r->m_hasHyphen)
+                text->setHasHyphen(true);
+        }
+    }
+
+    // We should have a root inline box.  It should be unconstructed and
+    // be the last continuation of our line list.
+    ASSERT(lastLineBox() && !lastLineBox()->isConstructed());
+
+    // Set the m_selectedChildren flag on the root inline box if one of the leaf inline box
+    // from the bidi runs walk above has a selection state.
+    if (rootHasSelectedChildren)
+        lastLineBox()->root()->setHasSelectedChildren(true);
+
+    // Set bits on our inline flow boxes that indicate which sides should
+    // paint borders/margins/padding.  This knowledge will ultimately be used when
+    // we determine the horizontal positions and widths of all the inline boxes on
+    // the line.
+    bool isLogicallyLastRunWrapped = bidiRuns.logicallyLastRun()->m_object && bidiRuns.logicallyLastRun()->m_object->isText() ? !reachedEndOfTextRenderer(bidiRuns) : true;
+    lastLineBox()->determineSpacingForFlowBoxes(lineInfo.isLastLine(), isLogicallyLastRunWrapped, bidiRuns.logicallyLastRun()->m_object);
+
+    // Now mark the line boxes as being constructed.
+    lastLineBox()->setConstructed();
+
+    // Return the last line.
+    return lastRootBox();
+}
+
+ETextAlign RenderBlock::textAlignmentForLine(bool endsWithSoftBreak) const
+{
+    ETextAlign alignment = style()->textAlign();
+    if (!endsWithSoftBreak && alignment == JUSTIFY)
+        alignment = TAAUTO;
+
+    return alignment;
+}
+
+static void updateLogicalWidthForLeftAlignedBlock(bool isLeftToRightDirection, BidiRun* trailingSpaceRun, float& logicalLeft, float& totalLogicalWidth, float availableLogicalWidth)
+{
+    // The direction of the block should determine what happens with wide lines.
+    // In particular with RTL blocks, wide lines should still spill out to the left.
+    if (isLeftToRightDirection) {
+        if (totalLogicalWidth > availableLogicalWidth && trailingSpaceRun)
+            trailingSpaceRun->m_box->setLogicalWidth(max<float>(0, trailingSpaceRun->m_box->logicalWidth() - totalLogicalWidth + availableLogicalWidth));
+        return;
+    }
+
+    if (trailingSpaceRun)
+        trailingSpaceRun->m_box->setLogicalWidth(0);
+    else if (totalLogicalWidth > availableLogicalWidth)
+        logicalLeft -= (totalLogicalWidth - availableLogicalWidth);
+}
+
+static void updateLogicalWidthForRightAlignedBlock(bool isLeftToRightDirection, BidiRun* trailingSpaceRun, float& logicalLeft, float& totalLogicalWidth, float availableLogicalWidth)
+{
+    // Wide lines spill out of the block based off direction.
+    // So even if text-align is right, if direction is LTR, wide lines should overflow out of the right
+    // side of the block.
+    if (isLeftToRightDirection) {
+        if (trailingSpaceRun) {
+            totalLogicalWidth -= trailingSpaceRun->m_box->logicalWidth();
+            trailingSpaceRun->m_box->setLogicalWidth(0);
+        }
+        if (totalLogicalWidth < availableLogicalWidth)
+            logicalLeft += availableLogicalWidth - totalLogicalWidth;
+        return;
+    }
+
+    if (totalLogicalWidth > availableLogicalWidth && trailingSpaceRun) {
+        trailingSpaceRun->m_box->setLogicalWidth(max<float>(0, trailingSpaceRun->m_box->logicalWidth() - totalLogicalWidth + availableLogicalWidth));
+        totalLogicalWidth -= trailingSpaceRun->m_box->logicalWidth();
+    } else
+        logicalLeft += availableLogicalWidth - totalLogicalWidth;
+}
+
+static void updateLogicalWidthForCenterAlignedBlock(bool isLeftToRightDirection, BidiRun* trailingSpaceRun, float& logicalLeft, float& totalLogicalWidth, float availableLogicalWidth)
+{
+    float trailingSpaceWidth = 0;
+    if (trailingSpaceRun) {
+        totalLogicalWidth -= trailingSpaceRun->m_box->logicalWidth();
+        trailingSpaceWidth = min(trailingSpaceRun->m_box->logicalWidth(), (availableLogicalWidth - totalLogicalWidth + 1) / 2);
+        trailingSpaceRun->m_box->setLogicalWidth(max<float>(0, trailingSpaceWidth));
+    }
+    if (isLeftToRightDirection)
+        logicalLeft += max<float>((availableLogicalWidth - totalLogicalWidth) / 2, 0);
+    else
+        logicalLeft += totalLogicalWidth > availableLogicalWidth ? (availableLogicalWidth - totalLogicalWidth) : (availableLogicalWidth - totalLogicalWidth) / 2 - trailingSpaceWidth;
+}
+
+void RenderBlock::setMarginsForRubyRun(BidiRun* run, RenderRubyRun* renderer, RenderObject* previousObject, const LineInfo& lineInfo)
+{
+    int startOverhang;
+    int endOverhang;
+    RenderObject* nextObject = 0;
+    for (BidiRun* runWithNextObject = run->next(); runWithNextObject; runWithNextObject = runWithNextObject->next()) {
+        if (!runWithNextObject->m_object->isPositioned() && !runWithNextObject->m_box->isLineBreak()) {
+            nextObject = runWithNextObject->m_object;
+            break;
+        }
+    }
+    renderer->getOverhang(lineInfo.isFirstLine(), renderer->style()->isLeftToRightDirection() ? previousObject : nextObject, renderer->style()->isLeftToRightDirection() ? nextObject : previousObject, startOverhang, endOverhang);
+    setMarginStartForChild(renderer, -startOverhang);
+    setMarginEndForChild(renderer, -endOverhang);
+}
+
+static inline float measureHyphenWidth(RenderText* renderer, const Font& font)
+{
+    RenderStyle* style = renderer->style();
+    return font.width(RenderBlock::constructTextRun(renderer, font, style->hyphenString().string(), style));
+}
+
+static inline void setLogicalWidthForTextRun(RootInlineBox* lineBox, BidiRun* run, RenderText* renderer, float xPos, const LineInfo& lineInfo,
+                                   GlyphOverflowAndFallbackFontsMap& textBoxDataMap, VerticalPositionCache& verticalPositionCache)
+{
+    HashSet<const SimpleFontData*> fallbackFonts;
+    GlyphOverflow glyphOverflow;
+    
+    // Always compute glyph overflow if the block's line-box-contain value is "glyphs".
+    if (lineBox->fitsToGlyphs()) {
+        // If we don't stick out of the root line's font box, then don't bother computing our glyph overflow. This optimization
+        // will keep us from computing glyph bounds in nearly all cases.
+        bool includeRootLine = lineBox->includesRootLineBoxFontOrLeading();
+        int baselineShift = lineBox->verticalPositionForBox(run->m_box, verticalPositionCache);
+        int rootDescent = includeRootLine ? lineBox->renderer()->style(lineInfo.isFirstLine())->font().fontMetrics().descent() : 0;
+        int rootAscent = includeRootLine ? lineBox->renderer()->style(lineInfo.isFirstLine())->font().fontMetrics().ascent() : 0;
+        int boxAscent = renderer->style(lineInfo.isFirstLine())->font().fontMetrics().ascent() - baselineShift;
+        int boxDescent = renderer->style(lineInfo.isFirstLine())->font().fontMetrics().descent() + baselineShift;
+        if (boxAscent > rootDescent ||  boxDescent > rootAscent)
+            glyphOverflow.computeBounds = true; 
+    }
+    
+    int hyphenWidth = 0;
+    if (toInlineTextBox(run->m_box)->hasHyphen()) {
+        const Font& font = renderer->style(lineInfo.isFirstLine())->font();
+        hyphenWidth = measureHyphenWidth(renderer, font);
+    }
+    run->m_box->setLogicalWidth(renderer->width(run->m_start, run->m_stop - run->m_start, xPos, lineInfo.isFirstLine(), &fallbackFonts, &glyphOverflow) + hyphenWidth);
+    if (!fallbackFonts.isEmpty()) {
+        ASSERT(run->m_box->isText());
+        GlyphOverflowAndFallbackFontsMap::iterator it = textBoxDataMap.add(toInlineTextBox(run->m_box), make_pair(Vector<const SimpleFontData*>(), GlyphOverflow())).first;
+        ASSERT(it->second.first.isEmpty());
+        copyToVector(fallbackFonts, it->second.first);
+        run->m_box->parent()->clearDescendantsHaveSameLineHeightAndBaseline();
+    }
+    if ((glyphOverflow.top || glyphOverflow.bottom || glyphOverflow.left || glyphOverflow.right)) {
+        ASSERT(run->m_box->isText());
+        GlyphOverflowAndFallbackFontsMap::iterator it = textBoxDataMap.add(toInlineTextBox(run->m_box), make_pair(Vector<const SimpleFontData*>(), GlyphOverflow())).first;
+        it->second.second = glyphOverflow;
+        run->m_box->clearKnownToHaveNoOverflow();
+    }
+}
+
+static inline void computeExpansionForJustifiedText(BidiRun* firstRun, BidiRun* trailingSpaceRun, Vector<unsigned, 16>& expansionOpportunities, unsigned expansionOpportunityCount, float& totalLogicalWidth, float availableLogicalWidth)
+{
+    if (!expansionOpportunityCount || availableLogicalWidth <= totalLogicalWidth)
+        return;
+
+    size_t i = 0;
+    for (BidiRun* r = firstRun; r; r = r->next()) {
+        if (!r->m_box || r == trailingSpaceRun)
+            continue;
+        
+        if (r->m_object->isText()) {
+            unsigned opportunitiesInRun = expansionOpportunities[i++];
+            
+            ASSERT(opportunitiesInRun <= expansionOpportunityCount);
+            
+            // Only justify text if whitespace is collapsed.
+            if (r->m_object->style()->collapseWhiteSpace()) {
+                InlineTextBox* textBox = toInlineTextBox(r->m_box);
+                int expansion = (availableLogicalWidth - totalLogicalWidth) * opportunitiesInRun / expansionOpportunityCount;
+                textBox->setExpansion(expansion);
+                totalLogicalWidth += expansion;
+            }
+            expansionOpportunityCount -= opportunitiesInRun;
+            if (!expansionOpportunityCount)
+                break;
+        }
+    }
+}
+
+void RenderBlock::updateLogicalWidthForAlignment(const ETextAlign& textAlign, BidiRun* trailingSpaceRun, float& logicalLeft, float& totalLogicalWidth, float& availableLogicalWidth, int expansionOpportunityCount)
+{
+    // Armed with the total width of the line (without justification),
+    // we now examine our text-align property in order to determine where to position the
+    // objects horizontally. The total width of the line can be increased if we end up
+    // justifying text.
+    switch (textAlign) {
+    case LEFT:
+    case WEBKIT_LEFT:
+        updateLogicalWidthForLeftAlignedBlock(style()->isLeftToRightDirection(), trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
+        break;
+    case JUSTIFY:
+        adjustInlineDirectionLineBounds(expansionOpportunityCount, logicalLeft, availableLogicalWidth);
+        if (expansionOpportunityCount) {
+            if (trailingSpaceRun) {
+                totalLogicalWidth -= trailingSpaceRun->m_box->logicalWidth();
+                trailingSpaceRun->m_box->setLogicalWidth(0);
+            }
+            break;
+        }
+        // fall through
+    case TAAUTO:
+        // for right to left fall through to right aligned
+        if (style()->isLeftToRightDirection()) {
+            if (totalLogicalWidth > availableLogicalWidth && trailingSpaceRun)
+                trailingSpaceRun->m_box->setLogicalWidth(max<float>(0, trailingSpaceRun->m_box->logicalWidth() - totalLogicalWidth + availableLogicalWidth));
+            break;
+        }
+    case RIGHT:
+    case WEBKIT_RIGHT:
+        updateLogicalWidthForRightAlignedBlock(style()->isLeftToRightDirection(), trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
+        break;
+    case CENTER:
+    case WEBKIT_CENTER:
+        updateLogicalWidthForCenterAlignedBlock(style()->isLeftToRightDirection(), trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
+        break;
+    case TASTART:
+        if (style()->isLeftToRightDirection())
+            updateLogicalWidthForLeftAlignedBlock(style()->isLeftToRightDirection(), trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
+        else
+            updateLogicalWidthForRightAlignedBlock(style()->isLeftToRightDirection(), trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
+        break;
+    case TAEND:
+        if (style()->isLeftToRightDirection())
+            updateLogicalWidthForRightAlignedBlock(style()->isLeftToRightDirection(), trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
+        else
+            updateLogicalWidthForLeftAlignedBlock(style()->isLeftToRightDirection(), trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth);
+        break;
+    }
+}
+
+void RenderBlock::computeInlineDirectionPositionsForLine(RootInlineBox* lineBox, const LineInfo& lineInfo, BidiRun* firstRun, BidiRun* trailingSpaceRun, bool reachedEnd,
+                                                         GlyphOverflowAndFallbackFontsMap& textBoxDataMap, VerticalPositionCache& verticalPositionCache)
+{
+    ETextAlign textAlign = textAlignmentForLine(!reachedEnd && !lineBox->endsWithBreak());
+    float logicalLeft = logicalLeftOffsetForLine(logicalHeight(), lineInfo.isFirstLine());
+    float availableLogicalWidth = logicalRightOffsetForLine(logicalHeight(), lineInfo.isFirstLine()) - logicalLeft;
+
+    bool needsWordSpacing = false;
+    float totalLogicalWidth = lineBox->getFlowSpacingLogicalWidth();
+    unsigned expansionOpportunityCount = 0;
+    bool isAfterExpansion = true;
+    Vector<unsigned, 16> expansionOpportunities;
+    RenderObject* previousObject = 0;
+
+    for (BidiRun* r = firstRun; r; r = r->next()) {
+        if (!r->m_box || r->m_object->isPositioned() || r->m_box->isLineBreak())
+            continue; // Positioned objects are only participating to figure out their
+                      // correct static x position.  They have no effect on the width.
+                      // Similarly, line break boxes have no effect on the width.
+        if (r->m_object->isText()) {
+            RenderText* rt = toRenderText(r->m_object);
+            if (textAlign == JUSTIFY && r != trailingSpaceRun) {
+                if (!isAfterExpansion)
+                    toInlineTextBox(r->m_box)->setCanHaveLeadingExpansion(true);
+                unsigned opportunitiesInRun = Font::expansionOpportunityCount(rt->characters() + r->m_start, r->m_stop - r->m_start, r->m_box->direction(), isAfterExpansion);
+                expansionOpportunities.append(opportunitiesInRun);
+                expansionOpportunityCount += opportunitiesInRun;
+            }
+
+            if (int length = rt->textLength()) {
+                if (!r->m_start && needsWordSpacing && isSpaceOrNewline(rt->characters()[r->m_start]))
+                    totalLogicalWidth += rt->style(lineInfo.isFirstLine())->font().wordSpacing();
+                needsWordSpacing = !isSpaceOrNewline(rt->characters()[r->m_stop - 1]) && r->m_stop == length;
+            }
+
+            setLogicalWidthForTextRun(lineBox, r, rt, totalLogicalWidth, lineInfo, textBoxDataMap, verticalPositionCache);
+        } else {
+            isAfterExpansion = false;
+            if (!r->m_object->isRenderInline()) {
+                RenderBox* renderBox = toRenderBox(r->m_object);
+                if (renderBox->isRubyRun())
+                    setMarginsForRubyRun(r, toRenderRubyRun(renderBox), previousObject, lineInfo);
+                r->m_box->setLogicalWidth(logicalWidthForChild(renderBox));
+                totalLogicalWidth += marginStartForChild(renderBox) + marginEndForChild(renderBox);
+            }
+        }
+
+        totalLogicalWidth += r->m_box->logicalWidth();
+        previousObject = r->m_object;
+    }
+
+    if (isAfterExpansion && !expansionOpportunities.isEmpty()) {
+        expansionOpportunities.last()--;
+        expansionOpportunityCount--;
+    }
+
+    updateLogicalWidthForAlignment(textAlign, trailingSpaceRun, logicalLeft, totalLogicalWidth, availableLogicalWidth, expansionOpportunityCount);
+
+    computeExpansionForJustifiedText(firstRun, trailingSpaceRun, expansionOpportunities, expansionOpportunityCount, totalLogicalWidth, availableLogicalWidth);
+
+    // The widths of all runs are now known.  We can now place every inline box (and
+    // compute accurate widths for the inline flow boxes).
+    needsWordSpacing = false;
+    lineBox->placeBoxesInInlineDirection(logicalLeft, needsWordSpacing, textBoxDataMap);
+}
+
+void RenderBlock::computeBlockDirectionPositionsForLine(RootInlineBox* lineBox, BidiRun* firstRun, GlyphOverflowAndFallbackFontsMap& textBoxDataMap,
+                                                        VerticalPositionCache& verticalPositionCache)
+{
+    setLogicalHeight(lineBox->alignBoxesInBlockDirection(logicalHeight(), textBoxDataMap, verticalPositionCache));
+
+    // Now make sure we place replaced render objects correctly.
+    for (BidiRun* r = firstRun; r; r = r->next()) {
+        ASSERT(r->m_box);
+        if (!r->m_box)
+            continue; // Skip runs with no line boxes.
+
+        // Align positioned boxes with the top of the line box.  This is
+        // a reasonable approximation of an appropriate y position.
+        if (r->m_object->isPositioned())
+            r->m_box->setLogicalTop(logicalHeight());
+
+        // Position is used to properly position both replaced elements and
+        // to update the static normal flow x/y of positioned elements.
+        if (r->m_object->isText())
+            toRenderText(r->m_object)->positionLineBox(r->m_box);
+        else if (r->m_object->isBox())
+            toRenderBox(r->m_object)->positionLineBox(r->m_box);
+    }
+    // Positioned objects and zero-length text nodes destroy their boxes in
+    // position(), which unnecessarily dirties the line.
+    lineBox->markDirty(false);
+}
+
+static inline bool isCollapsibleSpace(UChar character, RenderText* renderer)
+{
+    if (character == ' ' || character == '\t' || character == softHyphen)
+        return true;
+    if (character == '\n')
+        return !renderer->style()->preserveNewline();
+    if (character == noBreakSpace)
+        return renderer->style()->nbspMode() == SPACE;
+    return false;
+}
+
+
+static void setStaticPositions(RenderBlock* block, RenderBox* child)
+{
+    // FIXME: The math here is actually not really right. It's a best-guess approximation that
+    // will work for the common cases
+    RenderObject* containerBlock = child->container();
+    LayoutUnit blockHeight = block->logicalHeight();
+    if (containerBlock->isRenderInline()) {
+        // A relative positioned inline encloses us. In this case, we also have to determine our
+        // position as though we were an inline. Set |staticInlinePosition| and |staticBlockPosition| on the relative positioned
+        // inline so that we can obtain the value later.
+        toRenderInline(containerBlock)->layer()->setStaticInlinePosition(block->startAlignedOffsetForLine(child, blockHeight, false));
+        toRenderInline(containerBlock)->layer()->setStaticBlockPosition(blockHeight);
+    }
+
+    if (child->style()->isOriginalDisplayInlineType())
+        block->setStaticInlinePositionForChild(child, blockHeight, block->startAlignedOffsetForLine(child, blockHeight, false));
+    else
+        block->setStaticInlinePositionForChild(child, blockHeight, block->startOffsetForContent(blockHeight));
+    child->layer()->setStaticBlockPosition(blockHeight);
+}
+
+inline BidiRun* RenderBlock::handleTrailingSpaces(BidiRunList<BidiRun>& bidiRuns, BidiContext* currentContext)
+{
+    if (!bidiRuns.runCount()
+        || !bidiRuns.logicallyLastRun()->m_object->style()->breakOnlyAfterWhiteSpace()
+        || !bidiRuns.logicallyLastRun()->m_object->style()->autoWrap())
+        return 0;
+
+    BidiRun* trailingSpaceRun = bidiRuns.logicallyLastRun();
+    RenderObject* lastObject = trailingSpaceRun->m_object;
+    if (!lastObject->isText())
+        return 0;
+
+    RenderText* lastText = toRenderText(lastObject);
+    const UChar* characters = lastText->characters();
+    int firstSpace = trailingSpaceRun->stop();
+    while (firstSpace > trailingSpaceRun->start()) {
+        UChar current = characters[firstSpace - 1];
+        if (!isCollapsibleSpace(current, lastText))
+            break;
+        firstSpace--;
+    }
+    if (firstSpace == trailingSpaceRun->stop())
+        return 0;
+
+    TextDirection direction = style()->direction();
+    bool shouldReorder = trailingSpaceRun != (direction == LTR ? bidiRuns.lastRun() : bidiRuns.firstRun());
+    if (firstSpace != trailingSpaceRun->start()) {
+        BidiContext* baseContext = currentContext;
+        while (BidiContext* parent = baseContext->parent())
+            baseContext = parent;
+
+        BidiRun* newTrailingRun = new (renderArena()) BidiRun(firstSpace, trailingSpaceRun->m_stop, trailingSpaceRun->m_object, baseContext, OtherNeutral);
+        trailingSpaceRun->m_stop = firstSpace;
+        if (direction == LTR)
+            bidiRuns.addRun(newTrailingRun);
+        else
+            bidiRuns.prependRun(newTrailingRun);
+        trailingSpaceRun = newTrailingRun;
+        return trailingSpaceRun;
+    }
+    if (!shouldReorder)
+        return trailingSpaceRun;
+
+    if (direction == LTR) {
+        bidiRuns.moveRunToEnd(trailingSpaceRun);
+        trailingSpaceRun->m_level = 0;
+    } else {
+        bidiRuns.moveRunToBeginning(trailingSpaceRun);
+        trailingSpaceRun->m_level = 1;
+    }
+    return trailingSpaceRun;
+}
+
+void RenderBlock::appendFloatingObjectToLastLine(FloatingObject* floatingObject)
+{
+    ASSERT(!floatingObject->m_originatingLine);
+    floatingObject->m_originatingLine = lastRootBox();
+    lastRootBox()->appendFloat(floatingObject->renderer());
+}
+
+// FIXME: This should be a BidiStatus constructor or create method.
+static inline BidiStatus statusWithDirection(TextDirection textDirection)
+{
+    WTF::Unicode::Direction direction = textDirection == LTR ? LeftToRight : RightToLeft;
+    RefPtr<BidiContext> context = BidiContext::create(textDirection == LTR ? 0 : 1, direction, false, FromStyleOrDOM);
+
+    // This copies BidiStatus and may churn the ref on BidiContext. I doubt it matters.
+    return BidiStatus(direction, direction, direction, context.release());
+}
+
+// FIXME: BidiResolver should have this logic.
+static inline void constructBidiRuns(InlineBidiResolver& topResolver, BidiRunList<BidiRun>& bidiRuns, const InlineIterator& endOfLine, VisualDirectionOverride override, bool previousLineBrokeCleanly)
+{
+    // FIXME: We should pass a BidiRunList into createBidiRunsForLine instead
+    // of the resolver owning the runs.
+    ASSERT(&topResolver.runs() == &bidiRuns);
+    RenderObject* currentRoot = topResolver.position().root();
+    topResolver.createBidiRunsForLine(endOfLine, override, previousLineBrokeCleanly);
+
+    while (!topResolver.isolatedRuns().isEmpty()) {
+        // It does not matter which order we resolve the runs as long as we resolve them all.
+        BidiRun* isolatedRun = topResolver.isolatedRuns().last();
+        topResolver.isolatedRuns().removeLast();
+
+        RenderObject* startObj = isolatedRun->object();
+
+        // Only inlines make sense with unicode-bidi: isolate (blocks are already isolated).
+        // FIXME: Because enterIsolate is not passed a RenderObject, we have to crawl up the
+        // tree to see which parent inline is the isolate. We could change enterIsolate
+        // to take a RenderObject and do this logic there, but that would be a layering
+        // violation for BidiResolver (which knows nothing about RenderObject).
+        RenderInline* isolatedSpan = toRenderInline(containingIsolate(startObj, currentRoot));
+        InlineBidiResolver isolatedResolver;
+        isolatedResolver.setStatus(statusWithDirection(isolatedSpan->style()->direction()));
+
+        // FIXME: The fact that we have to construct an Iterator here
+        // currently prevents this code from moving into BidiResolver.
+        if (!bidiFirstSkippingEmptyInlines(isolatedSpan, &isolatedResolver))
+            continue;
+        // The starting position is the beginning of the first run within the isolate that was identified
+        // during the earlier call to createBidiRunsForLine. This can be but is not necessarily the
+        // first run within the isolate.
+        InlineIterator iter = InlineIterator(isolatedSpan, startObj, isolatedRun->m_start);
+        isolatedResolver.setPositionIgnoringNestedIsolates(iter);
+
+        // We stop at the next end of line; we may re-enter this isolate in the next call to constructBidiRuns().
+        // FIXME: What should end and previousLineBrokeCleanly be?
+        // rniwa says previousLineBrokeCleanly is just a WinIE hack and could always be false here?
+        isolatedResolver.createBidiRunsForLine(endOfLine, NoVisualOverride, previousLineBrokeCleanly);
+        // Note that we do not delete the runs from the resolver.
+        bidiRuns.replaceRunWithRuns(isolatedRun, isolatedResolver.runs());
+
+        // If we encountered any nested isolate runs, just move them
+        // to the top resolver's list for later processing.
+        if (!isolatedResolver.isolatedRuns().isEmpty()) {
+            topResolver.isolatedRuns().append(isolatedResolver.isolatedRuns());
+            isolatedResolver.isolatedRuns().clear();
+        }
+    }
+}
+
+// This function constructs line boxes for all of the text runs in the resolver and computes their position.
+RootInlineBox* RenderBlock::createLineBoxesFromBidiRuns(BidiRunList<BidiRun>& bidiRuns, const InlineIterator& end, LineInfo& lineInfo, VerticalPositionCache& verticalPositionCache, BidiRun* trailingSpaceRun)
+{
+    if (!bidiRuns.runCount())
+        return 0;
+
+    // FIXME: Why is this only done when we had runs?
+    lineInfo.setLastLine(!end.m_obj);
+
+    RootInlineBox* lineBox = constructLine(bidiRuns, lineInfo);
+    if (!lineBox)
+        return 0;
+
+    lineBox->setEndsWithBreak(lineInfo.previousLineBrokeCleanly());
+    
+#if ENABLE(SVG)
+    bool isSVGRootInlineBox = lineBox->isSVGRootInlineBox();
+#else
+    bool isSVGRootInlineBox = false;
+#endif
+    
+    GlyphOverflowAndFallbackFontsMap textBoxDataMap;
+    
+    // Now we position all of our text runs horizontally.
+    if (!isSVGRootInlineBox)
+        computeInlineDirectionPositionsForLine(lineBox, lineInfo, bidiRuns.firstRun(), trailingSpaceRun, end.atEnd(), textBoxDataMap, verticalPositionCache);
+    
+    // Now position our text runs vertically.
+    computeBlockDirectionPositionsForLine(lineBox, bidiRuns.firstRun(), textBoxDataMap, verticalPositionCache);
+    
+#if ENABLE(SVG)
+    // SVG text layout code computes vertical & horizontal positions on its own.
+    // Note that we still need to execute computeVerticalPositionsForLine() as
+    // it calls InlineTextBox::positionLineBox(), which tracks whether the box
+    // contains reversed text or not. If we wouldn't do that editing and thus
+    // text selection in RTL boxes would not work as expected.
+    if (isSVGRootInlineBox) {
+        ASSERT(isSVGText());
+        static_cast<SVGRootInlineBox*>(lineBox)->computePerCharacterLayoutInformation();
+    }
+#endif
+    
+    // Compute our overflow now.
+    lineBox->computeOverflow(lineBox->lineTop(), lineBox->lineBottom(), textBoxDataMap);
+    
+#if PLATFORM(MAC)
+    // Highlight acts as an overflow inflation.
+    if (style()->highlight() != nullAtom)
+        lineBox->addHighlightOverflow();
+#endif
+    return lineBox;
+}
+
+// Like LayoutState for layout(), LineLayoutState keeps track of global information
+// during an entire linebox tree layout pass (aka layoutInlineChildren).
+class LineLayoutState {
+public:
+    LineLayoutState(bool fullLayout, LayoutUnit& repaintLogicalTop, LayoutUnit& repaintLogicalBottom)
+        : m_lastFloat(0)
+        , m_endLine(0)
+        , m_floatIndex(0)
+        , m_endLineLogicalTop(0)
+        , m_endLineMatched(false)
+        , m_checkForFloatsFromLastLine(false)
+        , m_isFullLayout(fullLayout)
+        , m_repaintLogicalTop(repaintLogicalTop)
+        , m_repaintLogicalBottom(repaintLogicalBottom)
+        , m_usesRepaintBounds(false)
+    { }
+
+    void markForFullLayout() { m_isFullLayout = true; }
+    bool isFullLayout() const { return m_isFullLayout; }
+
+    bool usesRepaintBounds() const { return m_usesRepaintBounds; }
+
+    void setRepaintRange(LayoutUnit logicalHeight)
+    { 
+        m_usesRepaintBounds = true;
+        m_repaintLogicalTop = m_repaintLogicalBottom = logicalHeight; 
+    }
+    
+    void updateRepaintRangeFromBox(RootInlineBox* box, LayoutUnit paginationDelta = 0)
+    {
+        m_usesRepaintBounds = true;
+        m_repaintLogicalTop = min(m_repaintLogicalTop, box->logicalTopVisualOverflow() + min(paginationDelta, 0));
+        m_repaintLogicalBottom = max(m_repaintLogicalBottom, box->logicalBottomVisualOverflow() + max(paginationDelta, 0));
+    }
+    
+    bool endLineMatched() const { return m_endLineMatched; }
+    void setEndLineMatched(bool endLineMatched) { m_endLineMatched = endLineMatched; }
+
+    bool checkForFloatsFromLastLine() const { return m_checkForFloatsFromLastLine; }
+    void setCheckForFloatsFromLastLine(bool check) { m_checkForFloatsFromLastLine = check; }
+
+    LineInfo& lineInfo() { return m_lineInfo; }
+    const LineInfo& lineInfo() const { return m_lineInfo; }
+
+    int endLineLogicalTop() const { return m_endLineLogicalTop; }
+    void setEndLineLogicalTop(int logicalTop) { m_endLineLogicalTop = logicalTop; }
+
+    RootInlineBox* endLine() const { return m_endLine; }
+    void setEndLine(RootInlineBox* line) { m_endLine = line; }
+
+    RenderBlock::FloatingObject* lastFloat() const { return m_lastFloat; }
+    void setLastFloat(RenderBlock::FloatingObject* lastFloat) { m_lastFloat = lastFloat; }
+
+    Vector<RenderBlock::FloatWithRect>& floats() { return m_floats; }
+    
+    unsigned floatIndex() const { return m_floatIndex; }
+    void setFloatIndex(unsigned floatIndex) { m_floatIndex = floatIndex; }
+    
+private:
+    Vector<RenderBlock::FloatWithRect> m_floats;
+    RenderBlock::FloatingObject* m_lastFloat;
+    RootInlineBox* m_endLine;
+    LineInfo m_lineInfo;
+    unsigned m_floatIndex;
+    int m_endLineLogicalTop;
+    bool m_endLineMatched;
+    bool m_checkForFloatsFromLastLine;
+    
+    bool m_isFullLayout;
+
+    // FIXME: Should this be a range object instead of two ints?
+    LayoutUnit& m_repaintLogicalTop;
+    LayoutUnit& m_repaintLogicalBottom;
+
+    bool m_usesRepaintBounds;
+};
+
+static void deleteLineRange(LineLayoutState& layoutState, RenderArena* arena, RootInlineBox* startLine, RootInlineBox* stopLine = 0)
+{
+    RootInlineBox* boxToDelete = startLine;
+    while (boxToDelete && boxToDelete != stopLine) {
+        layoutState.updateRepaintRangeFromBox(boxToDelete);
+        // Note: deleteLineRange(renderArena(), firstRootBox()) is not identical to deleteLineBoxTree().
+        // deleteLineBoxTree uses nextLineBox() instead of nextRootBox() when traversing.
+        RootInlineBox* next = boxToDelete->nextRootBox();
+        boxToDelete->deleteLine(arena);
+        boxToDelete = next;
+    }
+}
+
+void RenderBlock::layoutRunsAndFloats(LineLayoutState& layoutState, bool hasInlineChild)
+{
+    // We want to skip ahead to the first dirty line
+    InlineBidiResolver resolver;
+    RootInlineBox* startLine = determineStartPosition(layoutState, resolver);
+
+    unsigned consecutiveHyphenatedLines = 0;
+    if (startLine) {
+        for (RootInlineBox* line = startLine->prevRootBox(); line && line->isHyphenated(); line = line->prevRootBox())
+            consecutiveHyphenatedLines++;
+    }
+
+    // FIXME: This would make more sense outside of this function, but since
+    // determineStartPosition can change the fullLayout flag we have to do this here. Failure to call
+    // determineStartPosition first will break fast/repaint/line-flow-with-floats-9.html.
+    if (layoutState.isFullLayout() && hasInlineChild && !selfNeedsLayout()) {
+        setNeedsLayout(true, false);  // Mark ourselves as needing a full layout. This way we'll repaint like
+        // we're supposed to.
+        RenderView* v = view();
+        if (v && !v->doingFullRepaint() && hasLayer()) {
+            // Because we waited until we were already inside layout to discover
+            // that the block really needed a full layout, we missed our chance to repaint the layer
+            // before layout started.  Luckily the layer has cached the repaint rect for its original
+            // position and size, and so we can use that to make a repaint happen now.
+            repaintUsingContainer(containerForRepaint(), layer()->repaintRect());
+        }
+    }
+
+    if (m_floatingObjects && !m_floatingObjects->set().isEmpty())
+        layoutState.setLastFloat(m_floatingObjects->set().last());
+
+    // We also find the first clean line and extract these lines.  We will add them back
+    // if we determine that we're able to synchronize after handling all our dirty lines.
+    InlineIterator cleanLineStart;
+    BidiStatus cleanLineBidiStatus;
+    if (!layoutState.isFullLayout() && startLine)
+        determineEndPosition(layoutState, startLine, cleanLineStart, cleanLineBidiStatus);
+
+    if (startLine) {
+        if (!layoutState.usesRepaintBounds())
+            layoutState.setRepaintRange(logicalHeight());
+        deleteLineRange(layoutState, renderArena(), startLine);
+    }
+
+    if (!layoutState.isFullLayout() && lastRootBox() && lastRootBox()->endsWithBreak()) {
+        // If the last line before the start line ends with a line break that clear floats,
+        // adjust the height accordingly.
+        // A line break can be either the first or the last object on a line, depending on its direction.
+        if (InlineBox* lastLeafChild = lastRootBox()->lastLeafChild()) {
+            RenderObject* lastObject = lastLeafChild->renderer();
+            if (!lastObject->isBR())
+                lastObject = lastRootBox()->firstLeafChild()->renderer();
+            if (lastObject->isBR()) {
+                EClear clear = lastObject->style()->clear();
+                if (clear != CNONE)
+                    newLine(clear);
+            }
+        }
+    }
+
+    layoutRunsAndFloatsInRange(layoutState, resolver, cleanLineStart, cleanLineBidiStatus, consecutiveHyphenatedLines);
+    linkToEndLineIfNeeded(layoutState);
+    repaintDirtyFloats(layoutState.floats());
+}
+
+void RenderBlock::layoutRunsAndFloatsInRange(LineLayoutState& layoutState, InlineBidiResolver& resolver, const InlineIterator& cleanLineStart, const BidiStatus& cleanLineBidiStatus, unsigned consecutiveHyphenatedLines)
+{
+    bool paginated = view()->layoutState() && view()->layoutState()->isPaginated();
+    LineMidpointState& lineMidpointState = resolver.midpointState();
+    InlineIterator end = resolver.position();
+    bool checkForEndLineMatch = layoutState.endLine();
+    LineBreakIteratorInfo lineBreakIteratorInfo;
+    VerticalPositionCache verticalPositionCache;
+
+    LineBreaker lineBreaker(this);
+
+    while (!end.atEnd()) {
+        // FIXME: Is this check necessary before the first iteration or can it be moved to the end?
+        if (checkForEndLineMatch) {
+            layoutState.setEndLineMatched(matchedEndLine(layoutState, resolver, cleanLineStart, cleanLineBidiStatus));
+            if (layoutState.endLineMatched()) {
+                resolver.setPosition(InlineIterator(resolver.position().root(), 0, 0), 0);
+                break;
+            }
+        }
+
+        lineMidpointState.reset();
+
+        layoutState.lineInfo().setEmpty(true);
+        layoutState.lineInfo().resetRunsFromLeadingWhitespace();
+
+        const InlineIterator oldEnd = end;
+        bool isNewUBAParagraph = layoutState.lineInfo().previousLineBrokeCleanly();
+        FloatingObject* lastFloatFromPreviousLine = (m_floatingObjects && !m_floatingObjects->set().isEmpty()) ? m_floatingObjects->set().last() : 0;
+        end = lineBreaker.nextLineBreak(resolver, layoutState.lineInfo(), lineBreakIteratorInfo, lastFloatFromPreviousLine, consecutiveHyphenatedLines);
+        if (resolver.position().atEnd()) {
+            // FIXME: We shouldn't be creating any runs in findNextLineBreak to begin with!
+            // Once BidiRunList is separated from BidiResolver this will not be needed.
+            resolver.runs().deleteRuns();
+            resolver.markCurrentRunEmpty(); // FIXME: This can probably be replaced by an ASSERT (or just removed).
+            layoutState.setCheckForFloatsFromLastLine(true);
+            resolver.setPosition(InlineIterator(resolver.position().root(), 0, 0), 0);
+            break;
+        }
+        ASSERT(end != resolver.position());
+
+        // This is a short-cut for empty lines.
+        if (layoutState.lineInfo().isEmpty()) {
+            if (lastRootBox())
+                lastRootBox()->setLineBreakInfo(end.m_obj, end.m_pos, resolver.status());
+        } else {
+            VisualDirectionOverride override = (style()->rtlOrdering() == VisualOrder ? (style()->direction() == LTR ? VisualLeftToRightOverride : VisualRightToLeftOverride) : NoVisualOverride);
+
+            if (isNewUBAParagraph && style()->unicodeBidi() == Plaintext && !resolver.context()->parent()) {
+                TextDirection direction = style()->direction();
+                determineParagraphDirection(direction, resolver.position());
+                resolver.setStatus(BidiStatus(direction, style()->unicodeBidi() == Override));
+            }
+            // FIXME: This ownership is reversed. We should own the BidiRunList and pass it to createBidiRunsForLine.
+            BidiRunList<BidiRun>& bidiRuns = resolver.runs();
+            constructBidiRuns(resolver, bidiRuns, end, override, layoutState.lineInfo().previousLineBrokeCleanly());
+            ASSERT(resolver.position() == end);
+
+            BidiRun* trailingSpaceRun = !layoutState.lineInfo().previousLineBrokeCleanly() ? handleTrailingSpaces(bidiRuns, resolver.context()) : 0;
+
+            if (bidiRuns.runCount() && lineBreaker.lineWasHyphenated()) {
+                bidiRuns.logicallyLastRun()->m_hasHyphen = true;
+                consecutiveHyphenatedLines++;
+            } else
+                consecutiveHyphenatedLines = 0;
+
+            // Now that the runs have been ordered, we create the line boxes.
+            // At the same time we figure out where border/padding/margin should be applied for
+            // inline flow boxes.
+
+            LayoutUnit oldLogicalHeight = logicalHeight();
+            RootInlineBox* lineBox = createLineBoxesFromBidiRuns(bidiRuns, end, layoutState.lineInfo(), verticalPositionCache, trailingSpaceRun);
+
+            bidiRuns.deleteRuns();
+            resolver.markCurrentRunEmpty(); // FIXME: This can probably be replaced by an ASSERT (or just removed).
+
+            if (lineBox) {
+                lineBox->setLineBreakInfo(end.m_obj, end.m_pos, resolver.status());
+                if (layoutState.usesRepaintBounds())
+                    layoutState.updateRepaintRangeFromBox(lineBox);
+
+                if (paginated) {
+                    LayoutUnit adjustment = 0;
+                    adjustLinePositionForPagination(lineBox, adjustment);
+                    if (adjustment) {
+                        LayoutUnit oldLineWidth = availableLogicalWidthForLine(oldLogicalHeight, layoutState.lineInfo().isFirstLine());
+                        lineBox->adjustBlockDirectionPosition(adjustment);
+                        if (layoutState.usesRepaintBounds())
+                            layoutState.updateRepaintRangeFromBox(lineBox);
+
+                        if (availableLogicalWidthForLine(oldLogicalHeight + adjustment, layoutState.lineInfo().isFirstLine()) != oldLineWidth) {
+                            // We have to delete this line, remove all floats that got added, and let line layout re-run.
+                            lineBox->deleteLine(renderArena());
+                            removeFloatingObjectsBelow(lastFloatFromPreviousLine, oldLogicalHeight);
+                            setLogicalHeight(oldLogicalHeight + adjustment);
+                            resolver.setPositionIgnoringNestedIsolates(oldEnd);
+                            end = oldEnd;
+                            continue;
+                        }
+
+                        setLogicalHeight(lineBox->lineBottomWithLeading());
+                    }
+                }
+            }
+
+            for (size_t i = 0; i < lineBreaker.positionedObjects().size(); ++i)
+                setStaticPositions(this, lineBreaker.positionedObjects()[i]);
+
+            layoutState.lineInfo().setFirstLine(false);
+            newLine(lineBreaker.clear());
+        }
+
+        if (m_floatingObjects && lastRootBox()) {
+            const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
+            FloatingObjectSetIterator it = floatingObjectSet.begin();
+            FloatingObjectSetIterator end = floatingObjectSet.end();
+            if (layoutState.lastFloat()) {
+                FloatingObjectSetIterator lastFloatIterator = floatingObjectSet.find(layoutState.lastFloat());
+                ASSERT(lastFloatIterator != end);
+                ++lastFloatIterator;
+                it = lastFloatIterator;
+            }
+            for (; it != end; ++it) {
+                FloatingObject* f = *it;
+                appendFloatingObjectToLastLine(f);
+                ASSERT(f->m_renderer == layoutState.floats()[layoutState.floatIndex()].object);
+                // If a float's geometry has changed, give up on syncing with clean lines.
+                if (layoutState.floats()[layoutState.floatIndex()].rect != f->frameRect())
+                    checkForEndLineMatch = false;
+                layoutState.setFloatIndex(layoutState.floatIndex() + 1);
+            }
+            layoutState.setLastFloat(!floatingObjectSet.isEmpty() ? floatingObjectSet.last() : 0);
+        }
+
+        lineMidpointState.reset();
+        resolver.setPosition(end, numberOfIsolateAncestors(end));
+    }
+}
+
+void RenderBlock::linkToEndLineIfNeeded(LineLayoutState& layoutState)
+{
+    if (layoutState.endLine()) {
+        if (layoutState.endLineMatched()) {
+            bool paginated = view()->layoutState() && view()->layoutState()->isPaginated();
+            // Attach all the remaining lines, and then adjust their y-positions as needed.
+            LayoutUnit delta = logicalHeight() - layoutState.endLineLogicalTop();
+            for (RootInlineBox* line = layoutState.endLine(); line; line = line->nextRootBox()) {
+                line->attachLine();
+                if (paginated) {
+                    delta -= line->paginationStrut();
+                    adjustLinePositionForPagination(line, delta);
+                }
+                if (delta) {
+                    layoutState.updateRepaintRangeFromBox(line, delta);
+                    line->adjustBlockDirectionPosition(delta);
+                }
+                if (Vector<RenderBox*>* cleanLineFloats = line->floatsPtr()) {
+                    Vector<RenderBox*>::iterator end = cleanLineFloats->end();
+                    for (Vector<RenderBox*>::iterator f = cleanLineFloats->begin(); f != end; ++f) {
+                        FloatingObject* floatingObject = insertFloatingObject(*f);
+                        ASSERT(!floatingObject->m_originatingLine);
+                        floatingObject->m_originatingLine = line;
+                        setLogicalHeight(logicalTopForChild(*f) - marginBeforeForChild(*f) + delta);
+                        positionNewFloats();
+                    }
+                }
+            }
+            setLogicalHeight(lastRootBox()->lineBottomWithLeading());
+        } else {
+            // Delete all the remaining lines.
+            deleteLineRange(layoutState, renderArena(), layoutState.endLine());
+        }
+    }
+    
+    if (m_floatingObjects && (layoutState.checkForFloatsFromLastLine() || positionNewFloats()) && lastRootBox()) {
+        // In case we have a float on the last line, it might not be positioned up to now.
+        // This has to be done before adding in the bottom border/padding, or the float will
+        // include the padding incorrectly. -dwh
+        if (layoutState.checkForFloatsFromLastLine()) {
+            int bottomVisualOverflow = lastRootBox()->logicalBottomVisualOverflow();
+            int bottomLayoutOverflow = lastRootBox()->logicalBottomLayoutOverflow();
+            TrailingFloatsRootInlineBox* trailingFloatsLineBox = new (renderArena()) TrailingFloatsRootInlineBox(this);
+            m_lineBoxes.appendLineBox(trailingFloatsLineBox);
+            trailingFloatsLineBox->setConstructed();
+            GlyphOverflowAndFallbackFontsMap textBoxDataMap;
+            VerticalPositionCache verticalPositionCache;
+            int blockLogicalHeight = logicalHeight();
+            trailingFloatsLineBox->alignBoxesInBlockDirection(blockLogicalHeight, textBoxDataMap, verticalPositionCache);
+            trailingFloatsLineBox->setLineTopBottomPositions(blockLogicalHeight, blockLogicalHeight, blockLogicalHeight, blockLogicalHeight);
+            trailingFloatsLineBox->setPaginatedLineWidth(availableLogicalWidthForContent(blockLogicalHeight));
+            IntRect logicalLayoutOverflow(0, blockLogicalHeight, 1, bottomLayoutOverflow - blockLogicalHeight);
+            IntRect logicalVisualOverflow(0, blockLogicalHeight, 1, bottomVisualOverflow - blockLogicalHeight);
+            trailingFloatsLineBox->setOverflowFromLogicalRects(logicalLayoutOverflow, logicalVisualOverflow, trailingFloatsLineBox->lineTop(), trailingFloatsLineBox->lineBottom());
+        }
+
+        const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
+        FloatingObjectSetIterator it = floatingObjectSet.begin();
+        FloatingObjectSetIterator end = floatingObjectSet.end();
+        if (layoutState.lastFloat()) {
+            FloatingObjectSetIterator lastFloatIterator = floatingObjectSet.find(layoutState.lastFloat());
+            ASSERT(lastFloatIterator != end);
+            ++lastFloatIterator;
+            it = lastFloatIterator;
+        }
+        for (; it != end; ++it)
+            appendFloatingObjectToLastLine(*it);
+        layoutState.setLastFloat(!floatingObjectSet.isEmpty() ? floatingObjectSet.last() : 0);
+    }
+}
+
+void RenderBlock::repaintDirtyFloats(Vector<FloatWithRect>& floats)
+{
+    size_t floatCount = floats.size();
+    // Floats that did not have layout did not repaint when we laid them out. They would have
+    // painted by now if they had moved, but if they stayed at (0, 0), they still need to be
+    // painted.
+    for (size_t i = 0; i < floatCount; ++i) {
+        if (!floats[i].everHadLayout) {
+            RenderBox* f = floats[i].object;
+            if (!f->x() && !f->y() && f->checkForRepaintDuringLayout())
+                f->repaint();
+        }
+    }
+}
+
+void RenderBlock::layoutInlineChildren(bool relayoutChildren, LayoutUnit& repaintLogicalTop, LayoutUnit& repaintLogicalBottom)
+{
+    m_overflow.clear();
+
+    setLogicalHeight(borderBefore() + paddingBefore());
+
+    // Figure out if we should clear out our line boxes.
+    // FIXME: Handle resize eventually!
+    bool isFullLayout = !firstLineBox() || selfNeedsLayout() || relayoutChildren;
+    LineLayoutState layoutState(isFullLayout, repaintLogicalTop, repaintLogicalBottom);
+
+    if (isFullLayout)
+        lineBoxes()->deleteLineBoxes(renderArena());
+
+    // Text truncation only kicks in if your overflow isn't visible and your text-overflow-mode isn't
+    // clip.
+    // FIXME: CSS3 says that descendants that are clipped must also know how to truncate.  This is insanely
+    // difficult to figure out (especially in the middle of doing layout), and is really an esoteric pile of nonsense
+    // anyway, so we won't worry about following the draft here.
+    bool hasTextOverflow = style()->textOverflow() && hasOverflowClip();
+
+    // Walk all the lines and delete our ellipsis line boxes if they exist.
+    if (hasTextOverflow)
+         deleteEllipsisLineBoxes();
+
+    if (firstChild()) {
+        // layout replaced elements
+        bool hasInlineChild = false;
+        for (InlineWalker walker(this); !walker.atEnd(); walker.advance()) {
+            RenderObject* o = walker.current();
+            if (!hasInlineChild && o->isInline())
+                hasInlineChild = true;
+
+            if (o->isReplaced() || o->isFloating() || o->isPositioned()) {
+                RenderBox* box = toRenderBox(o);
+
+                if (relayoutChildren || o->style()->width().isPercent() || o->style()->height().isPercent())
+                    o->setChildNeedsLayout(true, false);
+
+                // If relayoutChildren is set and the child has percentage padding or an embedded content box, we also need to invalidate the childs pref widths.
+                if (relayoutChildren && box->needsPreferredWidthsRecalculation())
+                    o->setPreferredLogicalWidthsDirty(true, false);
+
+                if (o->isPositioned())
+                    o->containingBlock()->insertPositionedObject(box);
+                else if (o->isFloating())
+                    layoutState.floats().append(FloatWithRect(box));
+                else if (layoutState.isFullLayout() || o->needsLayout()) {
+                    // Replaced elements
+                    toRenderBox(o)->dirtyLineBoxes(layoutState.isFullLayout());
+                    o->layoutIfNeeded();
+                }
+            } else if (o->isText() || (o->isRenderInline() && !walker.atEndOfInline())) {
+                if (!o->isText())
+                    toRenderInline(o)->updateAlwaysCreateLineBoxes(layoutState.isFullLayout());
+                if (layoutState.isFullLayout() || o->selfNeedsLayout())
+                    dirtyLineBoxesForRenderer(o, layoutState.isFullLayout());
+                o->setNeedsLayout(false);
+            }
+        }
+
+        layoutRunsAndFloats(layoutState, hasInlineChild);
+    }
+
+    // Expand the last line to accommodate Ruby and emphasis marks.
+    int lastLineAnnotationsAdjustment = 0;
+    if (lastRootBox()) {
+        int lowestAllowedPosition = max(lastRootBox()->lineBottom(), logicalHeight() + paddingAfter());
+        if (!style()->isFlippedLinesWritingMode())
+            lastLineAnnotationsAdjustment = lastRootBox()->computeUnderAnnotationAdjustment(lowestAllowedPosition);
+        else
+            lastLineAnnotationsAdjustment = lastRootBox()->computeOverAnnotationAdjustment(lowestAllowedPosition);
+    }
+
+    // Now add in the bottom border/padding.
+    setLogicalHeight(logicalHeight() + lastLineAnnotationsAdjustment + borderAfter() + paddingAfter() + scrollbarLogicalHeight());
+
+    if (!firstLineBox() && hasLineIfEmpty())
+        setLogicalHeight(logicalHeight() + lineHeight(true, isHorizontalWritingMode() ? HorizontalLine : VerticalLine, PositionOfInteriorLineBoxes));
+
+    // See if we have any lines that spill out of our block.  If we do, then we will possibly need to
+    // truncate text.
+    if (hasTextOverflow)
+        checkLinesForTextOverflow();
+}
+
+void RenderBlock::checkFloatsInCleanLine(RootInlineBox* line, Vector<FloatWithRect>& floats, size_t& floatIndex, bool& encounteredNewFloat, bool& dirtiedByFloat)
+{
+    Vector<RenderBox*>* cleanLineFloats = line->floatsPtr();
+    if (!cleanLineFloats)
+        return;
+
+    Vector<RenderBox*>::iterator end = cleanLineFloats->end();
+    for (Vector<RenderBox*>::iterator it = cleanLineFloats->begin(); it != end; ++it) {
+        RenderBox* floatingBox = *it;
+        floatingBox->layoutIfNeeded();
+        LayoutSize newSize(floatingBox->width() + floatingBox->marginLeft() + floatingBox->marginRight(), floatingBox->height() + floatingBox->marginTop() + floatingBox->marginBottom());
+        ASSERT(floatIndex < floats.size());
+        if (floats[floatIndex].object != floatingBox) {
+            encounteredNewFloat = true;
+            return;
+        }
+
+        if (floats[floatIndex].rect.size() != newSize) {
+            LayoutUnit floatTop = isHorizontalWritingMode() ? floats[floatIndex].rect.y() : floats[floatIndex].rect.x();
+            LayoutUnit floatHeight = isHorizontalWritingMode() ? max(floats[floatIndex].rect.height(), newSize.height())
+                                                                 : max(floats[floatIndex].rect.width(), newSize.width());
+            floatHeight = min(floatHeight, numeric_limits<LayoutUnit>::max() - floatTop);
+            line->markDirty();
+            markLinesDirtyInBlockRange(line->lineBottomWithLeading(), floatTop + floatHeight, line);
+            floats[floatIndex].rect.setSize(newSize);
+            dirtiedByFloat = true;
+        }
+        floatIndex++;
+    }
+}
+
+RootInlineBox* RenderBlock::determineStartPosition(LineLayoutState& layoutState, InlineBidiResolver& resolver)
+{
+    RootInlineBox* curr = 0;
+    RootInlineBox* last = 0;
+
+    // FIXME: This entire float-checking block needs to be broken into a new function.
+    bool dirtiedByFloat = false;
+    if (!layoutState.isFullLayout()) {
+        // Paginate all of the clean lines.
+        bool paginated = view()->layoutState() && view()->layoutState()->isPaginated();
+        LayoutUnit paginationDelta = 0;
+        size_t floatIndex = 0;
+        for (curr = firstRootBox(); curr && !curr->isDirty(); curr = curr->nextRootBox()) {
+            if (paginated) {
+                if (lineWidthForPaginatedLineChanged(curr)) {
+                    curr->markDirty();
+                    break;
+                }
+                paginationDelta -= curr->paginationStrut();
+                adjustLinePositionForPagination(curr, paginationDelta);
+                if (paginationDelta) {
+                    if (containsFloats() || !layoutState.floats().isEmpty()) {
+                        // FIXME: Do better eventually.  For now if we ever shift because of pagination and floats are present just go to a full layout.
+                        layoutState.markForFullLayout();
+                        break;
+                    }
+
+                    layoutState.updateRepaintRangeFromBox(curr, paginationDelta);
+                    curr->adjustBlockDirectionPosition(paginationDelta);
+                }
+            }
+
+            // If a new float has been inserted before this line or before its last known float, just do a full layout.
+            bool encounteredNewFloat = false;
+            checkFloatsInCleanLine(curr, layoutState.floats(), floatIndex, encounteredNewFloat, dirtiedByFloat);
+            if (encounteredNewFloat)
+                layoutState.markForFullLayout();
+
+            if (dirtiedByFloat || layoutState.isFullLayout())
+                break;
+        }
+        // Check if a new float has been inserted after the last known float.
+        if (!curr && floatIndex < layoutState.floats().size())
+            layoutState.markForFullLayout();
+    }
+
+    if (layoutState.isFullLayout()) {
+        // FIXME: This should just call deleteLineBoxTree, but that causes
+        // crashes for fast/repaint tests.
+        RenderArena* arena = renderArena();
+        curr = firstRootBox();
+        while (curr) {
+            // Note: This uses nextRootBox() insted of nextLineBox() like deleteLineBoxTree does.
+            RootInlineBox* next = curr->nextRootBox();
+            curr->deleteLine(arena);
+            curr = next;
+        }
+        ASSERT(!firstLineBox() && !lastLineBox());
+    } else {
+        if (curr) {
+            // We have a dirty line.
+            if (RootInlineBox* prevRootBox = curr->prevRootBox()) {
+                // We have a previous line.
+                if (!dirtiedByFloat && (!prevRootBox->endsWithBreak() || (prevRootBox->lineBreakObj()->isText() && prevRootBox->lineBreakPos() >= toRenderText(prevRootBox->lineBreakObj())->textLength())))
+                    // The previous line didn't break cleanly or broke at a newline
+                    // that has been deleted, so treat it as dirty too.
+                    curr = prevRootBox;
+            }
+        } else {
+            // No dirty lines were found.
+            // If the last line didn't break cleanly, treat it as dirty.
+            if (lastRootBox() && !lastRootBox()->endsWithBreak())
+                curr = lastRootBox();
+        }
+
+        // If we have no dirty lines, then last is just the last root box.
+        last = curr ? curr->prevRootBox() : lastRootBox();
+    }
+
+    unsigned numCleanFloats = 0;
+    if (!layoutState.floats().isEmpty()) {
+        LayoutUnit savedLogicalHeight = logicalHeight();
+        // Restore floats from clean lines.
+        RootInlineBox* line = firstRootBox();
+        while (line != curr) {
+            if (Vector<RenderBox*>* cleanLineFloats = line->floatsPtr()) {
+                Vector<RenderBox*>::iterator end = cleanLineFloats->end();
+                for (Vector<RenderBox*>::iterator f = cleanLineFloats->begin(); f != end; ++f) {
+                    FloatingObject* floatingObject = insertFloatingObject(*f);
+                    ASSERT(!floatingObject->m_originatingLine);
+                    floatingObject->m_originatingLine = line;
+                    setLogicalHeight(logicalTopForChild(*f) - marginBeforeForChild(*f));
+                    positionNewFloats();
+                    ASSERT(layoutState.floats()[numCleanFloats].object == *f);
+                    numCleanFloats++;
+                }
+            }
+            line = line->nextRootBox();
+        }
+        setLogicalHeight(savedLogicalHeight);
+    }
+    layoutState.setFloatIndex(numCleanFloats);
+
+    layoutState.lineInfo().setFirstLine(!last);
+    layoutState.lineInfo().setPreviousLineBrokeCleanly(!last || last->endsWithBreak());
+
+    if (last) {
+        setLogicalHeight(last->lineBottomWithLeading());
+        InlineIterator iter = InlineIterator(this, last->lineBreakObj(), last->lineBreakPos());
+        resolver.setPosition(iter, numberOfIsolateAncestors(iter));
+        resolver.setStatus(last->lineBreakBidiStatus());
+    } else {
+        TextDirection direction = style()->direction();
+        if (style()->unicodeBidi() == Plaintext) {
+            // FIXME: Why does "unicode-bidi: plaintext" bidiFirstIncludingEmptyInlines when all other line layout code uses bidiFirstSkippingEmptyInlines?
+            determineParagraphDirection(direction, InlineIterator(this, bidiFirstIncludingEmptyInlines(this), 0));
+        }
+        resolver.setStatus(BidiStatus(direction, style()->unicodeBidi() == Override));
+        InlineIterator iter = InlineIterator(this, bidiFirstSkippingEmptyInlines(this, &resolver), 0);
+        resolver.setPosition(iter, numberOfIsolateAncestors(iter));
+    }
+    return curr;
+}
+
+void RenderBlock::determineEndPosition(LineLayoutState& layoutState, RootInlineBox* startLine, InlineIterator& cleanLineStart, BidiStatus& cleanLineBidiStatus)
+{
+    ASSERT(!layoutState.endLine());
+    size_t floatIndex = layoutState.floatIndex();
+    RootInlineBox* last = 0;
+    for (RootInlineBox* curr = startLine->nextRootBox(); curr; curr = curr->nextRootBox()) {
+        if (!curr->isDirty()) {
+            bool encounteredNewFloat = false;
+            bool dirtiedByFloat = false;
+            checkFloatsInCleanLine(curr, layoutState.floats(), floatIndex, encounteredNewFloat, dirtiedByFloat);
+            if (encounteredNewFloat)
+                return;
+        }
+        if (curr->isDirty())
+            last = 0;
+        else if (!last)
+            last = curr;
+    }
+
+    if (!last)
+        return;
+
+    // At this point, |last| is the first line in a run of clean lines that ends with the last line
+    // in the block.
+
+    RootInlineBox* prev = last->prevRootBox();
+    cleanLineStart = InlineIterator(this, prev->lineBreakObj(), prev->lineBreakPos());
+    cleanLineBidiStatus = prev->lineBreakBidiStatus();
+    layoutState.setEndLineLogicalTop(prev->lineBottomWithLeading());
+
+    for (RootInlineBox* line = last; line; line = line->nextRootBox())
+        line->extractLine(); // Disconnect all line boxes from their render objects while preserving
+                             // their connections to one another.
+
+    layoutState.setEndLine(last);
+}
+
+bool RenderBlock::checkPaginationAndFloatsAtEndLine(LineLayoutState& layoutState)
+{
+    LayoutUnit lineDelta = logicalHeight() - layoutState.endLineLogicalTop();
+
+    bool paginated = view()->layoutState() && view()->layoutState()->isPaginated();
+    if (paginated && inRenderFlowThread()) {
+        // Check all lines from here to the end, and see if the hypothetical new position for the lines will result
+        // in a different available line width.
+        for (RootInlineBox* lineBox = layoutState.endLine(); lineBox; lineBox = lineBox->nextRootBox()) {
+            if (paginated) {
+                // This isn't the real move we're going to do, so don't update the line box's pagination
+                // strut yet.
+                LayoutUnit oldPaginationStrut = lineBox->paginationStrut();
+                lineDelta -= oldPaginationStrut;
+                adjustLinePositionForPagination(lineBox, lineDelta);
+                lineBox->setPaginationStrut(oldPaginationStrut);
+            }
+            if (lineWidthForPaginatedLineChanged(lineBox, lineDelta))
+                return false;
+        }
+    }
+    
+    if (!lineDelta || !m_floatingObjects)
+        return true;
+    
+    // See if any floats end in the range along which we want to shift the lines vertically.
+    LayoutUnit logicalTop = min(logicalHeight(), layoutState.endLineLogicalTop());
+
+    RootInlineBox* lastLine = layoutState.endLine();
+    while (RootInlineBox* nextLine = lastLine->nextRootBox())
+        lastLine = nextLine;
+
+    LayoutUnit logicalBottom = lastLine->lineBottomWithLeading() + abs(lineDelta);
+
+    const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
+    FloatingObjectSetIterator end = floatingObjectSet.end();
+    for (FloatingObjectSetIterator it = floatingObjectSet.begin(); it != end; ++it) {
+        FloatingObject* f = *it;
+        if (logicalBottomForFloat(f) >= logicalTop && logicalBottomForFloat(f) < logicalBottom)
+            return false;
+    }
+
+    return true;
+}
+
+bool RenderBlock::matchedEndLine(LineLayoutState& layoutState, const InlineBidiResolver& resolver, const InlineIterator& endLineStart, const BidiStatus& endLineStatus)
+{
+    if (resolver.position() == endLineStart) {
+        if (resolver.status() != endLineStatus)
+            return false;
+        return checkPaginationAndFloatsAtEndLine(layoutState);
+    }
+
+    // The first clean line doesn't match, but we can check a handful of following lines to try
+    // to match back up.
+    static int numLines = 8; // The # of lines we're willing to match against.
+    RootInlineBox* originalEndLine = layoutState.endLine();
+    RootInlineBox* line = originalEndLine;
+    for (int i = 0; i < numLines && line; i++, line = line->nextRootBox()) {
+        if (line->lineBreakObj() == resolver.position().m_obj && line->lineBreakPos() == resolver.position().m_pos) {
+            // We have a match.
+            if (line->lineBreakBidiStatus() != resolver.status())
+                return false; // ...but the bidi state doesn't match.
+            
+            bool matched = false;
+            RootInlineBox* result = line->nextRootBox();
+            layoutState.setEndLine(result);
+            if (result) {
+                layoutState.setEndLineLogicalTop(line->lineBottomWithLeading());
+                matched = checkPaginationAndFloatsAtEndLine(layoutState);
+            }
+
+            // Now delete the lines that we failed to sync.
+            deleteLineRange(layoutState, renderArena(), originalEndLine, result);
+            return matched;
+        }
+    }
+
+    return false;
+}
+
+static inline bool skipNonBreakingSpace(const InlineIterator& it, const LineInfo& lineInfo)
+{
+    if (it.m_obj->style()->nbspMode() != SPACE || it.current() != noBreakSpace)
+        return false;
+
+    // FIXME: This is bad.  It makes nbsp inconsistent with space and won't work correctly
+    // with m_minWidth/m_maxWidth.
+    // Do not skip a non-breaking space if it is the first character
+    // on a line after a clean line break (or on the first line, since previousLineBrokeCleanly starts off
+    // |true|).
+    if (lineInfo.isEmpty() && lineInfo.previousLineBrokeCleanly())
+        return false;
+
+    return true;
+}
+
+enum WhitespacePosition { LeadingWhitespace, TrailingWhitespace };
+static inline bool shouldCollapseWhiteSpace(const RenderStyle* style, const LineInfo& lineInfo, WhitespacePosition whitespacePosition)
+{
+    // CSS2 16.6.1
+    // If a space (U+0020) at the beginning of a line has 'white-space' set to 'normal', 'nowrap', or 'pre-line', it is removed.
+    // If a space (U+0020) at the end of a line has 'white-space' set to 'normal', 'nowrap', or 'pre-line', it is also removed.
+    // If spaces (U+0020) or tabs (U+0009) at the end of a line have 'white-space' set to 'pre-wrap', UAs may visually collapse them.
+    return style->collapseWhiteSpace()
+        || (whitespacePosition == TrailingWhitespace && style->whiteSpace() == PRE_WRAP && (!lineInfo.isEmpty() || !lineInfo.previousLineBrokeCleanly()));
+}
+
+static bool inlineFlowRequiresLineBox(RenderInline* flow, const LineInfo& lineInfo)
+{
+    // FIXME: Right now, we only allow line boxes for inlines that are truly empty.
+    // We need to fix this, though, because at the very least, inlines containing only
+    // ignorable whitespace should should also have line boxes.
+    if (!flow->document()->inQuirksMode() && flow->style(lineInfo.isFirstLine())->lineHeight() != flow->parent()->style(lineInfo.isFirstLine())->lineHeight())
+        return true;
+
+    return !flow->firstChild() && flow->hasInlineDirectionBordersPaddingOrMargin();
+}
+
+static bool requiresLineBox(const InlineIterator& it, const LineInfo& lineInfo = LineInfo(), WhitespacePosition whitespacePosition = LeadingWhitespace)
+{
+    if (it.m_obj->isFloatingOrPositioned())
+        return false;
+
+    if (it.m_obj->isRenderInline() && !inlineFlowRequiresLineBox(toRenderInline(it.m_obj), lineInfo))
+        return false;
+
+    if (!shouldCollapseWhiteSpace(it.m_obj->style(), lineInfo, whitespacePosition) || it.m_obj->isBR())
+        return true;
+
+    UChar current = it.current();
+    return current != ' ' && current != '\t' && current != softHyphen && (current != '\n' || it.m_obj->preservesNewline())
+    && !skipNonBreakingSpace(it, lineInfo);
+}
+
+bool RenderBlock::generatesLineBoxesForInlineChild(RenderObject* inlineObj)
+{
+    ASSERT(inlineObj->parent() == this);
+
+    InlineIterator it(this, inlineObj, 0);
+    // FIXME: We should pass correct value for WhitespacePosition.
+    while (!it.atEnd() && !requiresLineBox(it))
+        it.increment();
+
+    return !it.atEnd();
+}
+
+// FIXME: The entire concept of the skipTrailingWhitespace function is flawed, since we really need to be building
+// line boxes even for containers that may ultimately collapse away. Otherwise we'll never get positioned
+// elements quite right. In other words, we need to build this function's work into the normal line
+// object iteration process.
+// NB. this function will insert any floating elements that would otherwise
+// be skipped but it will not position them.
+void RenderBlock::LineBreaker::skipTrailingWhitespace(InlineIterator& iterator, const LineInfo& lineInfo)
+{
+    while (!iterator.atEnd() && !requiresLineBox(iterator, lineInfo, TrailingWhitespace)) {
+        RenderObject* object = iterator.m_obj;
+        if (object->isPositioned())
+            setStaticPositions(m_block, toRenderBox(object));
+        else if (object->isFloating())
+            m_block->insertFloatingObject(toRenderBox(object));
+        iterator.increment();
+    }
+}
+
+void RenderBlock::LineBreaker::skipLeadingWhitespace(InlineBidiResolver& resolver, LineInfo& lineInfo,
+                                                     FloatingObject* lastFloatFromPreviousLine, LineWidth& width)
+{
+    while (!resolver.position().atEnd() && !requiresLineBox(resolver.position(), lineInfo, LeadingWhitespace)) {
+        RenderObject* object = resolver.position().m_obj;
+        if (object->isPositioned()) {
+            setStaticPositions(m_block, toRenderBox(object));
+            if (object->style()->isOriginalDisplayInlineType()) {
+                resolver.runs().addRun(createRun(0, 1, object, resolver));
+                lineInfo.incrementRunsFromLeadingWhitespace();
+            }
+        } else if (object->isFloating())
+            m_block->positionNewFloatOnLine(m_block->insertFloatingObject(toRenderBox(object)), lastFloatFromPreviousLine, lineInfo, width);
+        resolver.increment();
+    }
+    resolver.commitExplicitEmbedding();
+}
+
+// This is currently just used for list markers and inline flows that have line boxes. Neither should
+// have an effect on whitespace at the start of the line.
+static bool shouldSkipWhitespaceAfterStartObject(RenderBlock* block, RenderObject* o, LineMidpointState& lineMidpointState)
+{
+    RenderObject* next = bidiNextSkippingEmptyInlines(block, o);
+    if (next && !next->isBR() && next->isText() && toRenderText(next)->textLength() > 0) {
+        RenderText* nextText = toRenderText(next);
+        UChar nextChar = nextText->characters()[0];
+        if (nextText->style()->isCollapsibleWhiteSpace(nextChar)) {
+            addMidpoint(lineMidpointState, InlineIterator(0, o, 0));
+            return true;
+        }
+    }
+
+    return false;
+}
+
+static inline float textWidth(RenderText* text, unsigned from, unsigned len, const Font& font, float xPos, bool isFixedPitch, bool collapseWhiteSpace)
+{
+    if (isFixedPitch || (!from && len == text->textLength()) || text->style()->hasTextCombine())
+        return text->width(from, len, font, xPos);
+
+    TextRun run = RenderBlock::constructTextRun(text, font, text->characters() + from, len, text->style());
+    run.setCharactersLength(text->textLength() - from);
+    ASSERT(run.charactersLength() >= run.length());
+
+    run.setAllowTabs(!collapseWhiteSpace);
+    run.setXPos(xPos);
+    return font.width(run);
+}
+
+static void tryHyphenating(RenderText* text, const Font& font, const AtomicString& localeIdentifier, unsigned consecutiveHyphenatedLines, int consecutiveHyphenatedLinesLimit, int minimumPrefixLength, int minimumSuffixLength, int lastSpace, int pos, float xPos, int availableWidth, bool isFixedPitch, bool collapseWhiteSpace, int lastSpaceWordSpacing, InlineIterator& lineBreak, int nextBreakable, bool& hyphenated)
+{
+    // Map 'hyphenate-limit-{before,after}: auto;' to 2.
+    if (minimumPrefixLength < 0)
+        minimumPrefixLength = 2;
+
+    if (minimumSuffixLength < 0)
+        minimumSuffixLength = 2;
+
+    if (pos - lastSpace <= minimumSuffixLength)
+        return;
+
+    if (consecutiveHyphenatedLinesLimit >= 0 && consecutiveHyphenatedLines >= static_cast<unsigned>(consecutiveHyphenatedLinesLimit))
+        return;
+
+    int hyphenWidth = measureHyphenWidth(text, font);
+
+    float maxPrefixWidth = availableWidth - xPos - hyphenWidth - lastSpaceWordSpacing;
+    // If the maximum width available for the prefix before the hyphen is small, then it is very unlikely
+    // that an hyphenation opportunity exists, so do not bother to look for it.
+    if (maxPrefixWidth <= font.pixelSize() * 5 / 4)
+        return;
+
+    TextRun run = RenderBlock::constructTextRun(text, font, text->characters() + lastSpace, pos - lastSpace, text->style());
+    run.setCharactersLength(text->textLength() - lastSpace);
+    ASSERT(run.charactersLength() >= run.length());
+
+    run.setAllowTabs(!collapseWhiteSpace);
+    run.setXPos(xPos + lastSpaceWordSpacing);
+
+    unsigned prefixLength = font.offsetForPosition(run, maxPrefixWidth, false);
+    if (prefixLength < static_cast<unsigned>(minimumPrefixLength))
+        return;
+
+    prefixLength = lastHyphenLocation(text->characters() + lastSpace, pos - lastSpace, min(prefixLength, static_cast<unsigned>(pos - lastSpace - minimumSuffixLength)) + 1, localeIdentifier);
+    if (!prefixLength || prefixLength < static_cast<unsigned>(minimumPrefixLength))
+        return;
+
+    // When lastSapce is a space, which it always is except sometimes at the beginning of a line or after collapsed
+    // space, it should not count towards hyphenate-limit-before.
+    if (prefixLength == static_cast<unsigned>(minimumPrefixLength)) {
+        UChar characterAtLastSpace = text->characters()[lastSpace];
+        if (characterAtLastSpace == ' ' || characterAtLastSpace == '\n' || characterAtLastSpace == '\t' || characterAtLastSpace == noBreakSpace)
+            return;
+    }
+
+    ASSERT(pos - lastSpace - prefixLength >= static_cast<unsigned>(minimumSuffixLength));
+
+#if !ASSERT_DISABLED
+    float prefixWidth = hyphenWidth + textWidth(text, lastSpace, prefixLength, font, xPos, isFixedPitch, collapseWhiteSpace) + lastSpaceWordSpacing;
+    ASSERT(xPos + prefixWidth <= availableWidth);
+#else
+    UNUSED_PARAM(isFixedPitch);
+#endif
+
+    lineBreak.moveTo(text, lastSpace + prefixLength, nextBreakable);
+    hyphenated = true;
+}
+
+class TrailingObjects {
+public:
+    TrailingObjects();
+    void setTrailingWhitespace(RenderText*);
+    void clear();
+    void appendBoxIfNeeded(RenderBox*);
+
+    enum CollapseFirstSpaceOrNot { DoNotCollapseFirstSpace, CollapseFirstSpace };
+
+    void updateMidpointsForTrailingBoxes(LineMidpointState&, const InlineIterator& lBreak, CollapseFirstSpaceOrNot);
+
+private:
+    RenderText* m_whitespace;
+    Vector<RenderBox*, 4> m_boxes;
+};
+
+TrailingObjects::TrailingObjects()
+    : m_whitespace(0)
+{
+}
+
+inline void TrailingObjects::setTrailingWhitespace(RenderText* whitespace)
+{
+    ASSERT(whitespace);
+    m_whitespace = whitespace;
+}
+
+inline void TrailingObjects::clear()
+{
+    m_whitespace = 0;
+    m_boxes.clear();
+}
+
+inline void TrailingObjects::appendBoxIfNeeded(RenderBox* box)
+{
+    if (m_whitespace)
+        m_boxes.append(box);
+}
+
+void TrailingObjects::updateMidpointsForTrailingBoxes(LineMidpointState& lineMidpointState, const InlineIterator& lBreak, CollapseFirstSpaceOrNot collapseFirstSpace)
+{
+    if (!m_whitespace)
+        return;
+
+    // This object is either going to be part of the last midpoint, or it is going to be the actual endpoint.
+    // In both cases we just decrease our pos by 1 level to exclude the space, allowing it to - in effect - collapse into the newline.
+    if (lineMidpointState.numMidpoints % 2) {
+        // Find the trailing space object's midpoint.
+        int trailingSpaceMidpoint = lineMidpointState.numMidpoints - 1;
+        for ( ; trailingSpaceMidpoint > 0 && lineMidpointState.midpoints[trailingSpaceMidpoint].m_obj != m_whitespace; --trailingSpaceMidpoint) { }
+        ASSERT(trailingSpaceMidpoint >= 0);
+        if (collapseFirstSpace == CollapseFirstSpace)
+            lineMidpointState.midpoints[trailingSpaceMidpoint].m_pos--;
+
+        // Now make sure every single trailingPositionedBox following the trailingSpaceMidpoint properly stops and starts
+        // ignoring spaces.
+        size_t currentMidpoint = trailingSpaceMidpoint + 1;
+        for (size_t i = 0; i < m_boxes.size(); ++i) {
+            if (currentMidpoint >= lineMidpointState.numMidpoints) {
+                // We don't have a midpoint for this box yet.
+                InlineIterator ignoreStart(0, m_boxes[i], 0);
+                addMidpoint(lineMidpointState, ignoreStart); // Stop ignoring.
+                addMidpoint(lineMidpointState, ignoreStart); // Start ignoring again.
+            } else {
+                ASSERT(lineMidpointState.midpoints[currentMidpoint].m_obj == m_boxes[i]);
+                ASSERT(lineMidpointState.midpoints[currentMidpoint + 1].m_obj == m_boxes[i]);
+            }
+            currentMidpoint += 2;
+        }
+    } else if (!lBreak.m_obj) {
+        ASSERT(m_whitespace->isText());
+        ASSERT(collapseFirstSpace == CollapseFirstSpace);
+        // Add a new end midpoint that stops right at the very end.
+        unsigned length = m_whitespace->textLength();
+        unsigned pos = length >= 2 ? length - 2 : UINT_MAX;
+        InlineIterator endMid(0, m_whitespace, pos);
+        addMidpoint(lineMidpointState, endMid);
+        for (size_t i = 0; i < m_boxes.size(); ++i) {
+            InlineIterator ignoreStart(0, m_boxes[i], 0);
+            addMidpoint(lineMidpointState, ignoreStart); // Stop ignoring spaces.
+            addMidpoint(lineMidpointState, ignoreStart); // Start ignoring again.
+        }
+    }
+}
+
+void RenderBlock::LineBreaker::reset()
+{
+    m_positionedObjects.clear();
+    m_hyphenated = false;
+    m_clear = CNONE;
+}
+
+InlineIterator RenderBlock::LineBreaker::nextLineBreak(InlineBidiResolver& resolver, LineInfo& lineInfo,
+    LineBreakIteratorInfo& lineBreakIteratorInfo, FloatingObject* lastFloatFromPreviousLine, unsigned consecutiveHyphenatedLines)
+{
+    reset();
+
+    ASSERT(resolver.position().root() == m_block);
+
+    bool appliedStartWidth = resolver.position().m_pos > 0;
+    bool includeEndWidth = true;
+    LineMidpointState& lineMidpointState = resolver.midpointState();
+
+    LineWidth width(m_block, lineInfo.isFirstLine());
+
+    skipLeadingWhitespace(resolver, lineInfo, lastFloatFromPreviousLine, width);
+
+    if (resolver.position().atEnd())
+        return resolver.position();
+
+    // This variable is used only if whitespace isn't set to PRE, and it tells us whether
+    // or not we are currently ignoring whitespace.
+    bool ignoringSpaces = false;
+    InlineIterator ignoreStart;
+
+    // This variable tracks whether the very last character we saw was a space.  We use
+    // this to detect when we encounter a second space so we know we have to terminate
+    // a run.
+    bool currentCharacterIsSpace = false;
+    bool currentCharacterIsWS = false;
+    TrailingObjects trailingObjects;
+
+    InlineIterator lBreak = resolver.position();
+
+    // FIXME: It is error-prone to split the position object out like this.
+    // Teach this code to work with objects instead of this split tuple.
+    InlineIterator current = resolver.position();
+    RenderObject* last = current.m_obj;
+    bool atStart = true;
+
+    bool startingNewParagraph = lineInfo.previousLineBrokeCleanly();
+    lineInfo.setPreviousLineBrokeCleanly(false);
+
+    bool autoWrapWasEverTrueOnLine = false;
+    bool floatsFitOnLine = true;
+
+    // Firefox and Opera will allow a table cell to grow to fit an image inside it under
+    // very specific circumstances (in order to match common WinIE renderings).
+    // Not supporting the quirk has caused us to mis-render some real sites. (See Bugzilla 10517.)
+    bool allowImagesToBreak = !m_block->document()->inQuirksMode() || !m_block->isTableCell() || !m_block->style()->logicalWidth().isIntrinsicOrAuto();
+
+    EWhiteSpace currWS = m_block->style()->whiteSpace();
+    EWhiteSpace lastWS = currWS;
+    while (current.m_obj) {
+        RenderObject* next = bidiNextSkippingEmptyInlines(m_block, current.m_obj);
+        if (next && next->parent() && !next->parent()->isDescendantOf(current.m_obj->parent()))
+            includeEndWidth = true;
+
+        currWS = current.m_obj->isReplaced() ? current.m_obj->parent()->style()->whiteSpace() : current.m_obj->style()->whiteSpace();
+        lastWS = last->isReplaced() ? last->parent()->style()->whiteSpace() : last->style()->whiteSpace();
+
+        bool autoWrap = RenderStyle::autoWrap(currWS);
+        autoWrapWasEverTrueOnLine = autoWrapWasEverTrueOnLine || autoWrap;
+
+#if ENABLE(SVG)
+        bool preserveNewline = current.m_obj->isSVGInlineText() ? false : RenderStyle::preserveNewline(currWS);
+#else
+        bool preserveNewline = RenderStyle::preserveNewline(currWS);
+#endif
+
+        bool collapseWhiteSpace = RenderStyle::collapseWhiteSpace(currWS);
+
+        if (current.m_obj->isBR()) {
+            if (width.fitsOnLine()) {
+                lBreak.moveToStartOf(current.m_obj);
+                lBreak.increment();
+
+                // A <br> always breaks a line, so don't let the line be collapsed
+                // away. Also, the space at the end of a line with a <br> does not
+                // get collapsed away.  It only does this if the previous line broke
+                // cleanly.  Otherwise the <br> has no effect on whether the line is
+                // empty or not.
+                if (startingNewParagraph)
+                    lineInfo.setEmpty(false, m_block, &width);
+                trailingObjects.clear();
+                lineInfo.setPreviousLineBrokeCleanly(true);
+
+                if (!lineInfo.isEmpty())
+                    m_clear = current.m_obj->style()->clear();
+            }
+            goto end;
+        }
+
+        if (current.m_obj->isPositioned()) {
+            // If our original display wasn't an inline type, then we can
+            // go ahead and determine our static inline position now.
+            RenderBox* box = toRenderBox(current.m_obj);
+            bool isInlineType = box->style()->isOriginalDisplayInlineType();
+            if (!isInlineType)
+                m_block->setStaticInlinePositionForChild(box, m_block->logicalHeight(), m_block->startOffsetForContent(m_block->logicalHeight()));
+            else  {
+                // If our original display was an INLINE type, then we can go ahead
+                // and determine our static y position now.
+                box->layer()->setStaticBlockPosition(m_block->logicalHeight());
+            }
+
+            // If we're ignoring spaces, we have to stop and include this object and
+            // then start ignoring spaces again.
+            if (isInlineType || current.m_obj->container()->isRenderInline()) {
+                if (ignoringSpaces) {
+                    ignoreStart.m_obj = current.m_obj;
+                    ignoreStart.m_pos = 0;
+                    addMidpoint(lineMidpointState, ignoreStart); // Stop ignoring spaces.
+                    addMidpoint(lineMidpointState, ignoreStart); // Start ignoring again.
+                }
+                trailingObjects.appendBoxIfNeeded(box);
+            } else
+                m_positionedObjects.append(box);
+        } else if (current.m_obj->isFloating()) {
+            RenderBox* floatBox = toRenderBox(current.m_obj);
+            FloatingObject* f = m_block->insertFloatingObject(floatBox);
+            // check if it fits in the current line.
+            // If it does, position it now, otherwise, position
+            // it after moving to next line (in newLine() func)
+            if (floatsFitOnLine && width.fitsOnLine(m_block->logicalWidthForFloat(f))) {
+                m_block->positionNewFloatOnLine(f, lastFloatFromPreviousLine, lineInfo, width);
+                if (lBreak.m_obj == current.m_obj) {
+                    ASSERT(!lBreak.m_pos);
+                    lBreak.increment();
+                }
+            } else
+                floatsFitOnLine = false;
+        } else if (current.m_obj->isRenderInline()) {
+            // Right now, we should only encounter empty inlines here.
+            ASSERT(!current.m_obj->firstChild());
+
+            RenderInline* flowBox = toRenderInline(current.m_obj);
+
+            // Now that some inline flows have line boxes, if we are already ignoring spaces, we need
+            // to make sure that we stop to include this object and then start ignoring spaces again.
+            // If this object is at the start of the line, we need to behave like list markers and
+            // start ignoring spaces.
+            if (inlineFlowRequiresLineBox(flowBox, lineInfo)) {
+                lineInfo.setEmpty(false, m_block, &width);
+                if (ignoringSpaces) {
+                    trailingObjects.clear();
+                    addMidpoint(lineMidpointState, InlineIterator(0, current.m_obj, 0)); // Stop ignoring spaces.
+                    addMidpoint(lineMidpointState, InlineIterator(0, current.m_obj, 0)); // Start ignoring again.
+                } else if (m_block->style()->collapseWhiteSpace() && resolver.position().m_obj == current.m_obj
+                    && shouldSkipWhitespaceAfterStartObject(m_block, current.m_obj, lineMidpointState)) {
+                    // Like with list markers, we start ignoring spaces to make sure that any
+                    // additional spaces we see will be discarded.
+                    currentCharacterIsSpace = true;
+                    currentCharacterIsWS = true;
+                    ignoringSpaces = true;
+                }
+            }
+
+            width.addUncommittedWidth(borderPaddingMarginStart(flowBox) + borderPaddingMarginEnd(flowBox));
+        } else if (current.m_obj->isReplaced()) {
+            RenderBox* replacedBox = toRenderBox(current.m_obj);
+
+            // Break on replaced elements if either has normal white-space.
+            if ((autoWrap || RenderStyle::autoWrap(lastWS)) && (!current.m_obj->isImage() || allowImagesToBreak)) {
+                width.commit();
+                lBreak.moveToStartOf(current.m_obj);
+            }
+
+            if (ignoringSpaces)
+                addMidpoint(lineMidpointState, InlineIterator(0, current.m_obj, 0));
+
+            lineInfo.setEmpty(false, m_block, &width);
+            ignoringSpaces = false;
+            currentCharacterIsSpace = false;
+            currentCharacterIsWS = false;
+            trailingObjects.clear();
+
+            // Optimize for a common case. If we can't find whitespace after the list
+            // item, then this is all moot.
+            LayoutUnit replacedLogicalWidth = m_block->logicalWidthForChild(replacedBox) + m_block->marginStartForChild(replacedBox) + m_block->marginEndForChild(replacedBox) + inlineLogicalWidth(current.m_obj);
+            if (current.m_obj->isListMarker()) {
+                if (m_block->style()->collapseWhiteSpace() && shouldSkipWhitespaceAfterStartObject(m_block, current.m_obj, lineMidpointState)) {
+                    // Like with inline flows, we start ignoring spaces to make sure that any
+                    // additional spaces we see will be discarded.
+                    currentCharacterIsSpace = true;
+                    currentCharacterIsWS = true;
+                    ignoringSpaces = true;
+                }
+                if (toRenderListMarker(current.m_obj)->isInside())
+                    width.addUncommittedWidth(replacedLogicalWidth);
+            } else
+                width.addUncommittedWidth(replacedLogicalWidth);
+            if (current.m_obj->isRubyRun())
+                width.applyOverhang(toRenderRubyRun(current.m_obj), last, next);
+        } else if (current.m_obj->isText()) {
+            if (!current.m_pos)
+                appliedStartWidth = false;
+
+            RenderText* t = toRenderText(current.m_obj);
+
+#if ENABLE(SVG)
+            bool isSVGText = t->isSVGInlineText();
+#endif
+
+            RenderStyle* style = t->style(lineInfo.isFirstLine());
+            if (style->hasTextCombine() && current.m_obj->isCombineText())
+                toRenderCombineText(current.m_obj)->combineText();
+
+            const Font& f = style->font();
+            bool isFixedPitch = f.isFixedPitch();
+            bool canHyphenate = style->hyphens() == HyphensAuto && WebCore::canHyphenate(style->locale());
+
+            int lastSpace = current.m_pos;
+            float wordSpacing = current.m_obj->style()->wordSpacing();
+            float lastSpaceWordSpacing = 0;
+
+            // Non-zero only when kerning is enabled, in which case we measure words with their trailing
+            // space, then subtract its width.
+            float wordTrailingSpaceWidth = f.typesettingFeatures() & Kerning ? f.width(constructTextRun(t, f, &space, 1, style)) + wordSpacing : 0;
+
+            float wrapW = width.uncommittedWidth() + inlineLogicalWidth(current.m_obj, !appliedStartWidth, true);
+            float charWidth = 0;
+            bool breakNBSP = autoWrap && current.m_obj->style()->nbspMode() == SPACE;
+            // Auto-wrapping text should wrap in the middle of a word only if it could not wrap before the word,
+            // which is only possible if the word is the first thing on the line, that is, if |w| is zero.
+            bool breakWords = current.m_obj->style()->breakWords() && ((autoWrap && !width.committedWidth()) || currWS == PRE);
+            bool midWordBreak = false;
+            bool breakAll = current.m_obj->style()->wordBreak() == BreakAllWordBreak && autoWrap;
+            float hyphenWidth = 0;
+
+            if (t->isWordBreak()) {
+                width.commit();
+                lBreak.moveToStartOf(current.m_obj);
+                ASSERT(current.m_pos == t->textLength());
+            }
+
+            for (; current.m_pos < t->textLength(); current.fastIncrementInTextNode()) {
+                bool previousCharacterIsSpace = currentCharacterIsSpace;
+                bool previousCharacterIsWS = currentCharacterIsWS;
+                UChar c = current.current();
+                currentCharacterIsSpace = c == ' ' || c == '\t' || (!preserveNewline && (c == '\n'));
+
+                if (!collapseWhiteSpace || !currentCharacterIsSpace)
+                    lineInfo.setEmpty(false, m_block, &width);
+
+                if (c == softHyphen && autoWrap && !hyphenWidth && style->hyphens() != HyphensNone) {
+                    hyphenWidth = measureHyphenWidth(t, f);
+                    width.addUncommittedWidth(hyphenWidth);
+                }
+
+                bool applyWordSpacing = false;
+
+                currentCharacterIsWS = currentCharacterIsSpace || (breakNBSP && c == noBreakSpace);
+
+                if ((breakAll || breakWords) && !midWordBreak) {
+                    wrapW += charWidth;
+                    bool midWordBreakIsBeforeSurrogatePair = U16_IS_LEAD(c) && current.m_pos + 1 < t->textLength() && U16_IS_TRAIL(t->characters()[current.m_pos + 1]);
+                    charWidth = textWidth(t, current.m_pos, midWordBreakIsBeforeSurrogatePair ? 2 : 1, f, width.committedWidth() + wrapW, isFixedPitch, collapseWhiteSpace);
+                    midWordBreak = width.committedWidth() + wrapW + charWidth > width.availableWidth();
+                }
+
+                if (lineBreakIteratorInfo.first != t) {
+                    lineBreakIteratorInfo.first = t;
+                    lineBreakIteratorInfo.second.reset(t->characters(), t->textLength(), style->locale());
+                }
+
+                bool betweenWords = c == '\n' || (currWS != PRE && !atStart && isBreakable(lineBreakIteratorInfo.second, current.m_pos, current.m_nextBreakablePosition, breakNBSP)
+                    && (style->hyphens() != HyphensNone || (current.previousInSameNode() != softHyphen)));
+
+                if (betweenWords || midWordBreak) {
+                    bool stoppedIgnoringSpaces = false;
+                    if (ignoringSpaces) {
+                        if (!currentCharacterIsSpace) {
+                            // Stop ignoring spaces and begin at this
+                            // new point.
+                            ignoringSpaces = false;
+                            lastSpaceWordSpacing = 0;
+                            lastSpace = current.m_pos; // e.g., "Foo    goo", don't add in any of the ignored spaces.
+                            addMidpoint(lineMidpointState, InlineIterator(0, current.m_obj, current.m_pos));
+                            stoppedIgnoringSpaces = true;
+                        } else {
+                            // Just keep ignoring these spaces.
+                            continue;
+                        }
+                    }
+
+                    float additionalTmpW;
+                    if (wordTrailingSpaceWidth && currentCharacterIsSpace)
+                        additionalTmpW = textWidth(t, lastSpace, current.m_pos + 1 - lastSpace, f, width.currentWidth(), isFixedPitch, collapseWhiteSpace) - wordTrailingSpaceWidth + lastSpaceWordSpacing;
+                    else
+                        additionalTmpW = textWidth(t, lastSpace, current.m_pos - lastSpace, f, width.currentWidth(), isFixedPitch, collapseWhiteSpace) + lastSpaceWordSpacing;
+                    width.addUncommittedWidth(additionalTmpW);
+                    if (!appliedStartWidth) {
+                        width.addUncommittedWidth(inlineLogicalWidth(current.m_obj, true, false));
+                        appliedStartWidth = true;
+                    }
+
+                    applyWordSpacing =  wordSpacing && currentCharacterIsSpace && !previousCharacterIsSpace;
+
+                    if (!width.committedWidth() && autoWrap && !width.fitsOnLine())
+                        width.fitBelowFloats();
+
+                    if (autoWrap || breakWords) {
+                        // If we break only after white-space, consider the current character
+                        // as candidate width for this line.
+                        bool lineWasTooWide = false;
+                        if (width.fitsOnLine() && currentCharacterIsWS && current.m_obj->style()->breakOnlyAfterWhiteSpace() && !midWordBreak) {
+                            float charWidth = textWidth(t, current.m_pos, 1, f, width.currentWidth(), isFixedPitch, collapseWhiteSpace) + (applyWordSpacing ? wordSpacing : 0);
+                            // Check if line is too big even without the extra space
+                            // at the end of the line. If it is not, do nothing.
+                            // If the line needs the extra whitespace to be too long,
+                            // then move the line break to the space and skip all
+                            // additional whitespace.
+                            if (!width.fitsOnLine(charWidth)) {
+                                lineWasTooWide = true;
+                                lBreak.moveTo(current.m_obj, current.m_pos, current.m_nextBreakablePosition);
+                                skipTrailingWhitespace(lBreak, lineInfo);
+                            }
+                        }
+                        if (lineWasTooWide || !width.fitsOnLine()) {
+                            if (canHyphenate && !width.fitsOnLine()) {
+                                tryHyphenating(t, f, style->locale(), consecutiveHyphenatedLines, m_block->style()->hyphenationLimitLines(), style->hyphenationLimitBefore(), style->hyphenationLimitAfter(), lastSpace, current.m_pos, width.currentWidth() - additionalTmpW, width.availableWidth(), isFixedPitch, collapseWhiteSpace, lastSpaceWordSpacing, lBreak, current.m_nextBreakablePosition, m_hyphenated);
+                                if (m_hyphenated)
+                                    goto end;
+                            }
+                            if (lBreak.atTextParagraphSeparator()) {
+                                if (!stoppedIgnoringSpaces && current.m_pos > 0) {
+                                    // We need to stop right before the newline and then start up again.
+                                    addMidpoint(lineMidpointState, InlineIterator(0, current.m_obj, current.m_pos - 1)); // Stop
+                                    addMidpoint(lineMidpointState, InlineIterator(0, current.m_obj, current.m_pos)); // Start
+                                }
+                                lBreak.increment();
+                                lineInfo.setPreviousLineBrokeCleanly(true);
+                            }
+                            if (lBreak.m_obj && lBreak.m_pos && lBreak.m_obj->isText() && toRenderText(lBreak.m_obj)->textLength() && toRenderText(lBreak.m_obj)->characters()[lBreak.m_pos - 1] == softHyphen && style->hyphens() != HyphensNone)
+                                m_hyphenated = true;
+                            goto end; // Didn't fit. Jump to the end.
+                        } else {
+                            if (!betweenWords || (midWordBreak && !autoWrap))
+                                width.addUncommittedWidth(-additionalTmpW);
+                            if (hyphenWidth) {
+                                // Subtract the width of the soft hyphen out since we fit on a line.
+                                width.addUncommittedWidth(-hyphenWidth);
+                                hyphenWidth = 0;
+                            }
+                        }
+                    }
+
+                    if (c == '\n' && preserveNewline) {
+                        if (!stoppedIgnoringSpaces && current.m_pos > 0) {
+                            // We need to stop right before the newline and then start up again.
+                            addMidpoint(lineMidpointState, InlineIterator(0, current.m_obj, current.m_pos - 1)); // Stop
+                            addMidpoint(lineMidpointState, InlineIterator(0, current.m_obj, current.m_pos)); // Start
+                        }
+                        lBreak.moveTo(current.m_obj, current.m_pos, current.m_nextBreakablePosition);
+                        lBreak.increment();
+                        lineInfo.setPreviousLineBrokeCleanly(true);
+                        return lBreak;
+                    }
+
+                    if (autoWrap && betweenWords) {
+                        width.commit();
+                        wrapW = 0;
+                        lBreak.moveTo(current.m_obj, current.m_pos, current.m_nextBreakablePosition);
+                        // Auto-wrapping text should not wrap in the middle of a word once it has had an
+                        // opportunity to break after a word.
+                        breakWords = false;
+                    }
+
+                    if (midWordBreak && !U16_IS_TRAIL(c) && !(category(c) & (Mark_NonSpacing | Mark_Enclosing | Mark_SpacingCombining))) {
+                        // Remember this as a breakable position in case
+                        // adding the end width forces a break.
+                        lBreak.moveTo(current.m_obj, current.m_pos, current.m_nextBreakablePosition);
+                        midWordBreak &= (breakWords || breakAll);
+                    }
+
+                    if (betweenWords) {
+                        lastSpaceWordSpacing = applyWordSpacing ? wordSpacing : 0;
+                        lastSpace = current.m_pos;
+                    }
+
+                    if (!ignoringSpaces && current.m_obj->style()->collapseWhiteSpace()) {
+                        // If we encounter a newline, or if we encounter a
+                        // second space, we need to go ahead and break up this
+                        // run and enter a mode where we start collapsing spaces.
+                        if (currentCharacterIsSpace && previousCharacterIsSpace) {
+                            ignoringSpaces = true;
+
+                            // We just entered a mode where we are ignoring
+                            // spaces. Create a midpoint to terminate the run
+                            // before the second space.
+                            addMidpoint(lineMidpointState, ignoreStart);
+                            trailingObjects.updateMidpointsForTrailingBoxes(lineMidpointState, InlineIterator(), TrailingObjects::DoNotCollapseFirstSpace);
+                        }
+                    }
+                } else if (ignoringSpaces) {
+                    // Stop ignoring spaces and begin at this
+                    // new point.
+                    ignoringSpaces = false;
+                    lastSpaceWordSpacing = applyWordSpacing ? wordSpacing : 0;
+                    lastSpace = current.m_pos; // e.g., "Foo    goo", don't add in any of the ignored spaces.
+                    addMidpoint(lineMidpointState, InlineIterator(0, current.m_obj, current.m_pos));
+                }
+
+#if ENABLE(SVG)
+                if (isSVGText && current.m_pos > 0) {
+                    // Force creation of new InlineBoxes for each absolute positioned character (those that start new text chunks).
+                    if (toRenderSVGInlineText(t)->characterStartsNewTextChunk(current.m_pos)) {
+                        addMidpoint(lineMidpointState, InlineIterator(0, current.m_obj, current.m_pos - 1));
+                        addMidpoint(lineMidpointState, InlineIterator(0, current.m_obj, current.m_pos));
+                    }
+                }
+#endif
+
+                if (currentCharacterIsSpace && !previousCharacterIsSpace) {
+                    ignoreStart.m_obj = current.m_obj;
+                    ignoreStart.m_pos = current.m_pos;
+                }
+
+                if (!currentCharacterIsWS && previousCharacterIsWS) {
+                    if (autoWrap && current.m_obj->style()->breakOnlyAfterWhiteSpace())
+                        lBreak.moveTo(current.m_obj, current.m_pos, current.m_nextBreakablePosition);
+                }
+
+                if (collapseWhiteSpace && currentCharacterIsSpace && !ignoringSpaces)
+                    trailingObjects.setTrailingWhitespace(toRenderText(current.m_obj));
+                else if (!current.m_obj->style()->collapseWhiteSpace() || !currentCharacterIsSpace)
+                    trailingObjects.clear();
+
+                atStart = false;
+            }
+
+            // IMPORTANT: current.m_pos is > length here!
+            float additionalTmpW = ignoringSpaces ? 0 : textWidth(t, lastSpace, current.m_pos - lastSpace, f, width.currentWidth(), isFixedPitch, collapseWhiteSpace) + lastSpaceWordSpacing;
+            width.addUncommittedWidth(additionalTmpW + inlineLogicalWidth(current.m_obj, !appliedStartWidth, includeEndWidth));
+            includeEndWidth = false;
+
+            if (!width.fitsOnLine()) {
+                if (canHyphenate)
+                    tryHyphenating(t, f, style->locale(), consecutiveHyphenatedLines, m_block->style()->hyphenationLimitLines(), style->hyphenationLimitBefore(), style->hyphenationLimitAfter(), lastSpace, current.m_pos, width.currentWidth() - additionalTmpW, width.availableWidth(), isFixedPitch, collapseWhiteSpace, lastSpaceWordSpacing, lBreak, current.m_nextBreakablePosition, m_hyphenated);
+
+                if (!m_hyphenated && lBreak.previousInSameNode() == softHyphen && style->hyphens() != HyphensNone)
+                    m_hyphenated = true;
+
+                if (m_hyphenated)
+                    goto end;
+            }
+        } else
+            ASSERT_NOT_REACHED();
+
+        bool checkForBreak = autoWrap;
+        if (width.committedWidth() && !width.fitsOnLine() && lBreak.m_obj && currWS == NOWRAP)
+            checkForBreak = true;
+        else if (next && current.m_obj->isText() && next->isText() && !next->isBR() && (autoWrap || (next->style()->autoWrap()))) {
+            if (currentCharacterIsSpace)
+                checkForBreak = true;
+            else {
+                RenderText* nextText = toRenderText(next);
+                if (nextText->textLength()) {
+                    UChar c = nextText->characters()[0];
+                    checkForBreak = (c == ' ' || c == '\t' || (c == '\n' && !next->preservesNewline()));
+                    // If the next item on the line is text, and if we did not end with
+                    // a space, then the next text run continues our word (and so it needs to
+                    // keep adding to |tmpW|. Just update and continue.
+                } else if (nextText->isWordBreak())
+                    checkForBreak = true;
+
+                if (!width.fitsOnLine() && !width.committedWidth())
+                    width.fitBelowFloats();
+
+                bool canPlaceOnLine = width.fitsOnLine() || !autoWrapWasEverTrueOnLine;
+                if (canPlaceOnLine && checkForBreak) {
+                    width.commit();
+                    lBreak.moveToStartOf(next);
+                }
+            }
+        }
+
+        if (checkForBreak && !width.fitsOnLine()) {
+            // if we have floats, try to get below them.
+            if (currentCharacterIsSpace && !ignoringSpaces && current.m_obj->style()->collapseWhiteSpace())
+                trailingObjects.clear();
+
+            if (width.committedWidth())
+                goto end;
+
+            width.fitBelowFloats();
+
+            // |width| may have been adjusted because we got shoved down past a float (thus
+            // giving us more room), so we need to retest, and only jump to
+            // the end label if we still don't fit on the line. -dwh
+            if (!width.fitsOnLine())
+                goto end;
+        }
+
+        if (!current.m_obj->isFloatingOrPositioned()) {
+            last = current.m_obj;
+            if (last->isReplaced() && autoWrap && (!last->isImage() || allowImagesToBreak) && (!last->isListMarker() || toRenderListMarker(last)->isInside())) {
+                width.commit();
+                lBreak.moveToStartOf(next);
+            }
+        }
+
+        // Clear out our character space bool, since inline <pre>s don't collapse whitespace
+        // with adjacent inline normal/nowrap spans.
+        if (!collapseWhiteSpace)
+            currentCharacterIsSpace = false;
+
+        current.moveToStartOf(next);
+        atStart = false;
+    }
+
+    if (width.fitsOnLine() || lastWS == NOWRAP)
+        lBreak.clear();
+
+ end:
+    if (lBreak == resolver.position() && (!lBreak.m_obj || !lBreak.m_obj->isBR())) {
+        // we just add as much as possible
+        if (m_block->style()->whiteSpace() == PRE) {
+            // FIXME: Don't really understand this case.
+            if (current.m_pos) {
+                // FIXME: This should call moveTo which would clear m_nextBreakablePosition
+                // this code as-is is likely wrong.
+                lBreak.m_obj = current.m_obj;
+                lBreak.m_pos = current.m_pos - 1;
+            } else
+                lBreak.moveTo(last, last->isText() ? last->length() : 0);
+        } else if (lBreak.m_obj) {
+            // Don't ever break in the middle of a word if we can help it.
+            // There's no room at all. We just have to be on this line,
+            // even though we'll spill out.
+            lBreak.moveTo(current.m_obj, current.m_pos);
+        }
+    }
+
+    // make sure we consume at least one char/object.
+    if (lBreak == resolver.position())
+        lBreak.increment();
+
+    // Sanity check our midpoints.
+    checkMidpoints(lineMidpointState, lBreak);
+
+    trailingObjects.updateMidpointsForTrailingBoxes(lineMidpointState, lBreak, TrailingObjects::CollapseFirstSpace);
+
+    // We might have made lBreak an iterator that points past the end
+    // of the object. Do this adjustment to make it point to the start
+    // of the next object instead to avoid confusing the rest of the
+    // code.
+    if (lBreak.m_pos > 0) {
+        lBreak.m_pos--;
+        lBreak.increment();
+    }
+
+    return lBreak;
+}
+
+void RenderBlock::addOverflowFromInlineChildren()
+{
+    LayoutUnit endPadding = hasOverflowClip() ? paddingEnd() : 0;
+    // FIXME: Need to find another way to do this, since scrollbars could show when we don't want them to.
+    if (hasOverflowClip() && !endPadding && node() && node()->rendererIsEditable() && node() == node()->rootEditableElement() && style()->isLeftToRightDirection())
+        endPadding = 1;
+    for (RootInlineBox* curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
+        addLayoutOverflow(curr->paddedLayoutOverflowRect(endPadding));
+        if (!hasOverflowClip())
+            addVisualOverflow(curr->visualOverflowRect(curr->lineTop(), curr->lineBottom()));
+    }
+}
+
+void RenderBlock::deleteEllipsisLineBoxes()
+{
+    for (RootInlineBox* curr = firstRootBox(); curr; curr = curr->nextRootBox())
+        curr->clearTruncation();
+}
+
+void RenderBlock::checkLinesForTextOverflow()
+{
+    // Determine the width of the ellipsis using the current font.
+    // FIXME: CSS3 says this is configurable, also need to use 0x002E (FULL STOP) if horizontal ellipsis is "not renderable"
+    const Font& font = style()->font();
+    DEFINE_STATIC_LOCAL(AtomicString, ellipsisStr, (&horizontalEllipsis, 1));
+    const Font& firstLineFont = firstLineStyle()->font();
+    LayoutUnit firstLineEllipsisWidth = firstLineFont.width(constructTextRun(this, firstLineFont, &horizontalEllipsis, 1, firstLineStyle()));
+    LayoutUnit ellipsisWidth = (font == firstLineFont) ? firstLineEllipsisWidth : font.width(constructTextRun(this, font, &horizontalEllipsis, 1, style()));
+
+    // For LTR text truncation, we want to get the right edge of our padding box, and then we want to see
+    // if the right edge of a line box exceeds that.  For RTL, we use the left edge of the padding box and
+    // check the left edge of the line box to see if it is less
+    // Include the scrollbar for overflow blocks, which means we want to use "contentWidth()"
+    bool ltr = style()->isLeftToRightDirection();
+    for (RootInlineBox* curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
+        LayoutUnit blockRightEdge = logicalRightOffsetForLine(curr->y(), curr == firstRootBox());
+        LayoutUnit blockLeftEdge = logicalLeftOffsetForLine(curr->y(), curr == firstRootBox());
+        LayoutUnit lineBoxEdge = ltr ? curr->x() + curr->logicalWidth() : curr->x();
+        if ((ltr && lineBoxEdge > blockRightEdge) || (!ltr && lineBoxEdge < blockLeftEdge)) {
+            // This line spills out of our box in the appropriate direction.  Now we need to see if the line
+            // can be truncated.  In order for truncation to be possible, the line must have sufficient space to
+            // accommodate our truncation string, and no replaced elements (images, tables) can overlap the ellipsis
+            // space.
+            LayoutUnit width = curr == firstRootBox() ? firstLineEllipsisWidth : ellipsisWidth;
+            LayoutUnit blockEdge = ltr ? blockRightEdge : blockLeftEdge;
+            if (curr->lineCanAccommodateEllipsis(ltr, blockEdge, lineBoxEdge, width))
+                curr->placeEllipsis(ellipsisStr, ltr, blockLeftEdge, blockRightEdge, width);
+        }
+    }
+}
+
+bool RenderBlock::positionNewFloatOnLine(FloatingObject* newFloat, FloatingObject* lastFloatFromPreviousLine, LineInfo& lineInfo, LineWidth& width)
+{
+    if (!positionNewFloats())
+        return false;
+
+    width.shrinkAvailableWidthForNewFloatIfNeeded(newFloat);
+
+    // We only connect floats to lines for pagination purposes if the floats occur at the start of
+    // the line and the previous line had a hard break (so this line is either the first in the block
+    // or follows a <br>).
+    if (!newFloat->m_paginationStrut || !lineInfo.previousLineBrokeCleanly() || !lineInfo.isEmpty())
+        return true;
+
+    const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
+    ASSERT(floatingObjectSet.last() == newFloat);
+
+    LayoutUnit floatLogicalTop = logicalTopForFloat(newFloat);
+    int paginationStrut = newFloat->m_paginationStrut;
+
+    if (floatLogicalTop - paginationStrut != logicalHeight() + lineInfo.floatPaginationStrut())
+        return true;
+
+    FloatingObjectSetIterator it = floatingObjectSet.end();
+    --it; // Last float is newFloat, skip that one.
+    FloatingObjectSetIterator begin = floatingObjectSet.begin();
+    while (it != begin) {
+        --it;
+        FloatingObject* f = *it;
+        if (f == lastFloatFromPreviousLine)
+            break;
+        if (logicalTopForFloat(f) == logicalHeight() + lineInfo.floatPaginationStrut()) {
+            f->m_paginationStrut += paginationStrut;
+            RenderBox* o = f->m_renderer;
+            setLogicalTopForChild(o, logicalTopForChild(o) + marginBeforeForChild(o) + paginationStrut);
+            if (o->isRenderBlock())
+                toRenderBlock(o)->setChildNeedsLayout(true, false);
+            o->layoutIfNeeded();
+            // Save the old logical top before calling removePlacedObject which will set
+            // isPlaced to false. Otherwise it will trigger an assert in logicalTopForFloat.
+            LayoutUnit oldLogicalTop = logicalTopForFloat(f);
+            m_floatingObjects->removePlacedObject(f);
+            setLogicalTopForFloat(f, oldLogicalTop + paginationStrut);
+            m_floatingObjects->addPlacedObject(f);
+        }
+    }
+
+    // Just update the line info's pagination strut without altering our logical height yet. If the line ends up containing
+    // no content, then we don't want to improperly grow the height of the block.
+    lineInfo.setFloatPaginationStrut(lineInfo.floatPaginationStrut() + paginationStrut);
+    return true;
+}
+
+LayoutUnit RenderBlock::startAlignedOffsetForLine(RenderBox* child, LayoutUnit position, bool firstLine)
+{
+    ETextAlign textAlign = style()->textAlign();
+
+    if (textAlign == TAAUTO)
+        return startOffsetForLine(position, firstLine);
+
+    // updateLogicalWidthForAlignment() handles the direction of the block so no need to consider it here
+    float logicalLeft;
+    float availableLogicalWidth;
+    logicalLeft = logicalLeftOffsetForLine(logicalHeight(), false);
+    availableLogicalWidth = logicalRightOffsetForLine(logicalHeight(), false) - logicalLeft;
+    float totalLogicalWidth = logicalWidthForChild(child);
+    updateLogicalWidthForAlignment(textAlign, 0l, logicalLeft, totalLogicalWidth, availableLogicalWidth, 0);
+
+    if (!style()->isLeftToRightDirection())
+        return logicalWidth() - (logicalLeft + totalLogicalWidth);
+    return logicalLeft;
+}
+
+}