anchor.diff:  
               model.selection = model.data[0];
               return new Future(() {
  -              final foundSelected = dom.document.querySelector('#bindSelection .selected');
  +              final foundSelected =
  +                  dom.document.querySelector('#bindSelection .selected');
                 expect(foundSelected.innerHtml, contains(model.data[0].value));
               });
             });
  
positive.code: 
          test('update selection from model', () {
            final template =
                dom.document.querySelector('#bindSelectionTemplate') as AutoBindingElement;
            final model = template.model = new MyModel();
            final done1 = expectAsync(() {});
  
            return new Future(() {
              final list = dom.document.querySelector('#bindSelection') as CoreList;
  
  // TODO(zoechi) check if this event should be fired when selection was changed
  // probably not because the doc says `Fired when an item element is tapped`
  // but it is handy during debugging of the test (remove this code when the problem is fixed)
  //            list.on['core-activate'].first.then((e) {
  //              expect((e.detail as CoreActivateEvent).data, equals(model.data[0]));
  //              done1();
  
negative.code: import 'package:polymer/polymer.dart';
  import 'package:unittest/unittest.dart';
  import 'package:unittest/html_config.dart' show useHtmlConfiguration;
  import 'package:core_elements/core_list_dart.dart' show CoreList,
      CoreActivateEvent;
  
  class Item {
    String value;
  