Fixed another dart2js code emitting error and enabled tests that now work

tools/dom/templates/html/impl/impl_Element.darttemplate

 // 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.
 
 part of $LIBRARYNAME;
 
 class _ChildrenElementList extends ListBase<Element>
     implements NodeListWrapper {
   // Raw Element.
   final Element _element;
@@ skipping 803 matching lines @@
   **/
   @Experimental()
   @SupportedBrowser(SupportedBrowser.CHROME, '36')
   AnimationPlayer animate(Iterable<Map<String, dynamic>> frames, [timing]) {
     if (frames is! Iterable || !(frames.every((x) => x is Map))) {
       throw new ArgumentError("The frames parameter should be a List of Maps "
           "with frame information");
     }
     var convertedFrames = frames;
     if (convertedFrames is Iterable) {
+$if DART2JS
+      convertedFrames = frames.map(convertDartToNative_Dictionary).toList();
+$else
       convertedFrames = convertDartToNative_List(
           frames.map(convertDartToNative_Dictionary).toList());
+$endif
     }
     var convertedTiming = timing;
     if (convertedTiming is Map) {
       convertedTiming = convertDartToNative_Dictionary(convertedTiming);
     }
     return convertedTiming == null
       ? _animate(convertedFrames)
       : _animate(convertedFrames, convertedTiming);
   }
 
@@ skipping 874 matching lines @@
   const ScrollAlignment._internal(this._value);
   toString() => 'ScrollAlignment.$_value';
 
   /// Attempt to align the element to the top of the scrollable area.
   static const TOP = const ScrollAlignment._internal('TOP');
   /// Attempt to center the element in the scrollable area.
   static const CENTER = const ScrollAlignment._internal('CENTER');
   /// Attempt to align the element to the bottom of the scrollable area.
   static const BOTTOM = const ScrollAlignment._internal('BOTTOM');
 }