anchor.diff:        /* Test 5: Multiple errors */
         @font-face {
             font-family: myfont5;
  -          src: url('resources/IntentionallyMissingFile.otf'), url(data:application/x-truetype-font,) format(truetype);
  +          src: url('resources/IntentionallyMissingFile.otf'), url(data:application/x-truetype-font,));
         }
         </style>
         ''', treeSanitizer: new NullTreeSanitizer());
  
positive.code:   onLoadingError(e) {
      firedEvents.add(e.type);
      event = e;
      shouldBe(event.fontfaces.length, 1);
      failedFonts = e.fontfaces.map((face){return face.family;}).toList()..sort();
      shouldBeList(failedFonts, ['myfont2']);
      finish();
    }
  
  
negative.code:       /* Test 3: Empty data url */
        @font-face {
            font-family: myfont3;
            src: url(data:application/x-truetype-font,);
        }
  
        /* Test 4: Download error followed by existing local font */
  