update elements and fix some bugs

test/common.dart

 // Copyright (c) 2015, 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 iron_elements.test.mock_interactions;
 
 import 'dart:async';
 import 'dart:html';
 import 'dart:js';
 import 'package:polymer_elements/iron_test_helpers.dart' as test_helpers;
 
 /// Used imports: [test_helpers]
 final JsObject _MockInteractionsJs = context['MockInteractions'];
 
 class Point {
   num x;
   num y;
 
+  Point(this.x, this.y);
+
   Point.fromJsObject(JsObject object)
       : x = object['x'],
         y = object['y'];
 
   Map toMap() => {'x': x, 'y': y};
   JsObject toJsObject() => new JsObject.jsify(toMap());
 
   bool isApproximatelyEqualTo(other) {
     return this.x.round() == other.x.round() &&
         this.y.round() == other.y.round();
@@ skipping 125 matching lines @@
 
 Future requestAnimationFrame() {
   var completer = new Completer();
   window.requestAnimationFrame((done) {
     completer.complete();
   });
   return completer.future;
 }
 
 List keysOf(JsObject object) => context['Object'].callMethod('keys', [object]);
+