anchor.diff:  class SparkUIAccess {
     static SparkUIAccess _instance;
   
  -  static SparkUIAccess get instance {
  -    if (_instance == null) _instance = new SparkUIAccess();
  +  factory SparkUIAccess() {
  +    if (_instance == null) _instance = new SparkUIAccess._internal();
       return _instance;
     }
  +
  +  SparkUIAccess._internal();
   
     SparkPolymerUI get _ui => document.querySelector('#topUi');
     Element getUIElement(String selectors) => _ui.getShadowDomElement(selectors);
  
positive.code: //      });
  //    });
  //  });
    SparkUIAccess scriptable = new SparkUIAccess();
    SparkUITester sparkTester = new SparkUITester(scriptable);
  
    group('new-project dialog', () {
      test('open and close the dialog via x button', () {
  
negative.code: }
  
  class SparkUITester {
    SparkUIAccess get sparkAccess => new SparkUIAccess();
  
    SparkUITester();
  
    Future openAndCloseWithX(MenuItemAccess menuItem) {
      DialogTester dialogTester = new DialogTester(menuItem.dialog);
  