Fix dwc extension with latest js-interop, small fix to dwc, and updates to

lib/src/utils.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.
 
 library utils;
 
 import 'dart:coreimpl';
 import 'package:web_components/src/messages.dart';
 
 /**
@@ skipping 15 matching lines @@
 /**
  * Invokes [callback], logs how long it took to execute in ms, and returns
  * whatever [callback] returns. The log message will be printed if [printTime]
  * is true.
  */
 time(String logMessage, callback(), {bool printTime: false}) {
   final watch = new Stopwatch();
   watch.start();
   var result = callback();
   watch.stop();
-  final duration = watch.elapsedInMs();
+  final duration = watch.elapsedMilliseconds;
   if (printTime) {
     _printMessage(logMessage, duration);
   }
   return result;
 }
 
 /**
  * Invokes [callback], logs how long it takes from the moment [callback] is
  * executed until the future it returns is completed. Returns the future
  * returned by [callback]. The log message will be printed if [printTime]
  * is true.
  */
 Future asyncTime(String logMessage, Future callback(),
                  {bool printTime: false}) {
   final watch = new Stopwatch();
   watch.start();
   return callback()..then((_) {
     watch.stop();
-    final duration = watch.elapsedInMs();
+    final duration = watch.elapsedMilliseconds;
     if (printTime) {
       _printMessage(logMessage, duration);
     }
   });
 }
 
 void _printMessage(String logMessage, int duration) {
   var buf = new StringBuffer();
   buf.add(logMessage);
   for (int i = logMessage.length; i < 60; i++) buf.add(' ');
@@ skipping 44 matching lines @@
       _pending--;
       if (_pending == 0) {
         _pending = _FINISHED;
         _completer.complete(futures);
       }
     });
   }
 
   Future<List> get future => _completer.future;
 }