iconview: Avoid usage of gdk_window_get_device_position() during DnD

Just use the last coordinates given on XdndPosition/drag_motion() in
order to trigger scrolling.

When running on Xwayland, the pointer position is unknown at this
stage on the X11 side, so the coordinates given here are bogus.
This change avoids both roundtrips and this situation.

https://bugzilla.gnome.org/show_bug.cgi?id=749679

1 files changed, 9 insertions, 23 deletions

diff --git a/gtk/gtkiconview.c b/gtk/gtkiconview.c
index f11fed149b..705356d02c 100644
--- a/gtk/gtkiconview.c
+++ b/gtk/gtkiconview.c
@@ -6208,8 +6208,7 @@ remove_scroll_timeout (GtkIconView *icon_view)
 }
 
 static void
-gtk_icon_view_autoscroll (GtkIconView *icon_view,
-                          GdkDevice   *device)
+gtk_icon_view_autoscroll (GtkIconView *icon_view)
 {
   GdkWindow *window;
   gint px, py, width, height;
@@ -6217,7 +6216,8 @@ gtk_icon_view_autoscroll (GtkIconView *icon_view,
 
   window = gtk_widget_get_window (GTK_WIDGET (icon_view));
 
-  gdk_window_get_device_position (window, device, &px, &py, NULL);
+  px = icon_view->priv->event_last_x;
+  py = icon_view->priv->event_last_y;
   gdk_window_get_geometry (window, NULL, NULL, &width, &height);
 
   /* see if we are near the edge. */
@@ -6238,27 +6238,14 @@ gtk_icon_view_autoscroll (GtkIconView *icon_view,
                               gtk_adjustment_get_value (icon_view->priv->hadjustment) + hoffset);
 }
 
-typedef struct {
-  GtkIconView *icon_view;
-  GdkDevice   *device;
-} DragScrollData;
-
 static gboolean
-drag_scroll_timeout (gpointer datap)
+drag_scroll_timeout (gpointer data)
 {
-  DragScrollData *data = datap;
-
-  gtk_icon_view_autoscroll (data->icon_view, data->device);
+  gtk_icon_view_autoscroll (data);
 
   return TRUE;
 }
 
-static void
-drag_scroll_data_free (DragScrollData *data)
-{
-  g_slice_free (DragScrollData, data);
-}
-
 static gboolean
 set_destination (GtkIconView    *icon_view,
 		 GdkDragContext *context,
@@ -6638,6 +6625,9 @@ gtk_icon_view_drag_motion (GtkWidget      *widget,
   if (!set_destination (icon_view, context, x, y, &suggested_action, &target))
     return FALSE;
 
+  icon_view->priv->event_last_x = x;
+  icon_view->priv->event_last_y = y;
+
   gtk_icon_view_get_drag_dest_item (icon_view, &path, &pos);
 
   /* we only know this *after* set_desination_row */
@@ -6652,12 +6642,8 @@ gtk_icon_view_drag_motion (GtkWidget      *widget,
     {
       if (icon_view->priv->scroll_timeout_id == 0)
 	{
-          DragScrollData *data = g_slice_new (DragScrollData);
-          data->icon_view = icon_view;
-          data->device = gdk_drag_context_get_device (context);
-
 	  icon_view->priv->scroll_timeout_id =
-	    gdk_threads_add_timeout_full (G_PRIORITY_DEFAULT, 50, drag_scroll_timeout, data, (GDestroyNotify) drag_scroll_data_free);
+	    gdk_threads_add_timeout (50, drag_scroll_timeout, icon_view);
 	  g_source_set_name_by_id (icon_view->priv->scroll_timeout_id, "[gtk+] drag_scroll_timeout");
 	}