Change Duration to take proper named optional parameters.

runtime/lib/date_patch.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 // Dart core library.
 
 // VM implementation of DateImplementation.
 patch class DateImplementation {
   /* patch */ DateImplementation(int year,
                                  [int month = 1,
                                   int day = 1,
@@ skipping 13 matching lines @@
       : isUtc = false,
         millisecondsSinceEpoch = _getCurrentMs() {
   }
 
   /* patch */ String get timeZoneName {
     if (isUtc) return "UTC";
     return _timeZoneName(millisecondsSinceEpoch);
   }
 
   /* patch */ Duration get timeZoneOffset {
-    if (isUtc) return new Duration(0);
+    if (isUtc) return new Duration();

[Lasse Reichstein Nielsen, 2012/09/13 09:30:46]

If not introducing the zero-duration, be consistent and use milliseconds: 0
here.

[kasperl, 2012/09/13 09:45:50]

I'm reluctant to start refactoring these things while I'm still trying to get
through all the code and "upgrade" it to the new optional parameter syntax and
semantics.

This is just the first of a ton of changes to the core libraries that we need to
do to enable the new semantics of positional optional parameters.

     int offsetInSeconds = _timeZoneOffsetInSeconds(millisecondsSinceEpoch);
     return new Duration(seconds: offsetInSeconds);
   }
 
   /* patch */ int get year => _decomposeIntoYearMonthDay(_localDateInUtcMs)[0];
 
   /* patch */ int get month => _decomposeIntoYearMonthDay(_localDateInUtcMs)[1];
 
   /* patch */ int get day => _decomposeIntoYearMonthDay(_localDateInUtcMs)[2];
 
@@ skipping 270 matching lines @@
 
   static String _timeZoneNameForClampedSeconds(int secondsSinceEpoch)
       native "DateNatives_timeZoneName";
 
   static int _timeZoneOffsetInSecondsForClampedSeconds(int secondsSinceEpoch)
       native "DateNatives_timeZoneOffsetInSeconds";
 
   static int _localTimeZoneAdjustmentInSeconds()
       native "DateNatives_localTimeZoneAdjustmentInSeconds";
 }