anchor.diff:      });
     });
   
  -  group('--iron-image-width, --iron-image-height', () {
  +  group('--iron-image-width', () {
       var fixedWidthContainer;
       var fixedWidthIronImage;
  -    var fixedHeightContainer;
  -    var fixedHeightIronImage;
   
       setUp(() {
         fixedWidthContainer = fixture('FixedWidthContainer');
         fixedWidthIronImage = fixedWidthContainer.querySelector('iron-image');
  -      fixedHeightContainer = fixture('FixedHeightContainer');
  -      fixedHeightIronImage = fixedHeightContainer.querySelector('iron-image');
       });
   
  -    test('100% width image fills container', () {
  +    test('100% width image fills container', ()  {
         Completer done = new Completer();
  -      fixedWidthIronImage.$['img'].on['load'].take(1).listen((Event e) {
  +      fixedWidthIronImage.$['img'].on['load'].take(1).listen((Event e) async {
           //fixedWidthIronImage.$.img.removeEventListener('load', onLoadedChanged);
           Polymer.updateStyles();
  +
  +        await wait(1);
   
           var containerRect = fixedWidthContainer.getBoundingClientRect();
           var ironImageRect = fixedWidthIronImage.getBoundingClientRect();
  
positive.code:       return done.future;
      });
  
      test('100% height image fills container', () {
        Completer done = new Completer();
        fixedHeightIronImage.$['img'].on['load'].take(1).listen((Event e) {
  
negative.code:         var containerRect = fixedHeightContainer.getBoundingClientRect();
          var ironImageRect = fixedHeightIronImage.getBoundingClientRect();
          var wrappedImageRect =
          fixedHeightIronImage.$['img'].getBoundingClientRect();
  
          expect(containerRect.height, closeTo(500, 0.5));
          expect(ironImageRect.height, closeTo(500, 0.5));
  