Revert "SERVER-13874 Make mongo::Milliseconds et al. aliases for equivalent stdx::chrono types."

This reverts commit 9aac625685811873ffbc2d3e8d09531eff1ce10e.

Committed in error.

3 files changed, 10 insertions, 7 deletions

diff --git a/src/mongo/db/pipeline/expression.cpp b/src/mongo/db/pipeline/expression.cpp
index e8c121c2b04..defc38d8c12 100644
--- a/src/mongo/db/pipeline/expression.cpp
+++ b/src/mongo/db/pipeline/expression.cpp
@@ -422,7 +422,7 @@ namespace {
         if (haveDate) {
             if (totalType == NumberDouble)
                 longTotal = static_cast<long long>(doubleTotal);
-            return Value(Date_t::fromMillisSinceEpoch(longTotal));
+            return Value(Date_t(longTotal));
         }
         else if (totalType == NumberLong) {
             return Value(longTotal);
@@ -2548,7 +2548,7 @@ namespace {
             }
             else if (rhs.numeric()) {
                 long long millisSinceEpoch = lhs.getDate() - rhs.coerceToLong();
-                return Value(Date_t::fromMillisSinceEpoch(millisSinceEpoch));
+                return Value(Date_t(millisSinceEpoch));
             }
             else {
                 uasserted(16613, str::stream() << "cant $subtract a "
diff --git a/src/mongo/db/pipeline/value.cpp b/src/mongo/db/pipeline/value.cpp
index c949601ac4d..b156d290613 100644
--- a/src/mongo/db/pipeline/value.cpp
+++ b/src/mongo/db/pipeline/value.cpp
@@ -186,7 +186,8 @@ namespace mongo {
             break;
 
         case Date:
-            _storage.dateValue = elem.date().toMillisSinceEpoch();
+            // this is really signed but typed as unsigned for historical reasons
+            _storage.dateValue = static_cast<long long>(elem.date().millis);
             break;
 
         case RegEx: {
@@ -287,7 +288,7 @@ namespace mongo {
         case NumberDouble: return builder << val.getDouble();
         case String:       return builder << val.getStringData();
         case Bool:         return builder << val.getBool();
-        case Date:         return builder << Date_t::fromMillisSinceEpoch(val.getDate());
+        case Date:         return builder << Date_t(val.getDate());
         case bsonTimestamp:    return builder << val.getTimestamp();
         case Object:       return builder << val.getDocument();
         case Symbol:       return builder << BSONSymbol(val.getStringData());
@@ -1017,7 +1018,7 @@ namespace mongo {
         case NumberLong:   return Value(buf.read<long long>());
         case NumberDouble: return Value(buf.read<double>());
         case Bool:         return Value(bool(buf.read<char>()));
-        case Date:         return Value(Date_t::fromMillisSinceEpoch(buf.read<long long>()));
+        case Date:         return Value(Date_t(buf.read<long long>()));
         case bsonTimestamp:  return Value(buf.read<Timestamp>());
 
         // types that are like strings
diff --git a/src/mongo/db/pipeline/value.h b/src/mongo/db/pipeline/value.h
index ecc66719d11..5324cc1b432 100644
--- a/src/mongo/db/pipeline/value.h
+++ b/src/mongo/db/pipeline/value.h
@@ -91,7 +91,9 @@ namespace mongo {
         explicit Value(const UndefinedLabeler&)   : _storage(Undefined) {} // BSONUndefined
         explicit Value(const MinKeyLabeler&)      : _storage(MinKey) {}    // MINKEY
         explicit Value(const MaxKeyLabeler&)      : _storage(MaxKey) {}    // MAXKEY
-        explicit Value(const Date_t& date) : _storage(Date, date.toMillisSinceEpoch()) {}
+        explicit Value(const Date_t& date)
+            : _storage(Date, static_cast<long long>(date.millis)) // millis really signed
+        {}
 
         // TODO: add an unsafe version that can share storage with the BSONElement
         /// Deep-convert from BSONElement to Value
@@ -315,7 +317,7 @@ namespace mongo {
 
     inline Timestamp Value::getTimestamp() const {
         verify(getType() == bsonTimestamp);
-        return Timestamp(_storage.timestampValue);
+        return Date_t(_storage.timestampValue);
     }
 
     inline const char* Value::getRegex() const {