anchor.diff:  
       var toolbar = new ActionBar(
         children: [
  -        new Icon(key: 'menu', style: _iconStyle,
  -            size: 24,
  -            type: 'navigation/menu_white')
  -          ..events.listen('gesturetap', _drawerController.toggle),
  +        new EventTarget(
  +          new Icon(key: 'menu', style: _iconStyle,
  +              size: 24,
  +              type: 'navigation/menu_white'),
  +          onGestureTap: _drawerController.toggle
  +        ),
           new Container(
             style: _titleStyle,
             children: [title]
           ),
  -        new Icon(key: 'search', style: _iconStyle,
  -            size: 24,
  -            type: 'action/search_white')
  -          ..events.listen('gesturetap', _handleSearchClick),
  -        new Icon(key: 'more_white', style: _iconStyle,
  -            size: 24,
  -            type: 'navigation/more_vert_white')
  -          ..events.listen('gesturetap', _handleMenuClick),
  +        new EventTarget(
  +          new Icon(key: 'search', style: _iconStyle,
  +              size: 24,
  +              type: 'action/search_white'),
  +          onGestureTap: _handleSearchClick
  +        ),
  +        new EventTarget(
  +          new Icon(key: 'more_white', style: _iconStyle,
  +              size: 24,
  +              type: 'navigation/more_vert_white'),
  +          onGestureTap: _handleMenuClick
  +        )
         ]
       );
   
  
positive.code: 
    void _handleMenuClick(_) {
      setState(() {
        _menuController.open();
      });
    }
  
negative.code: class StocksApp extends App {
  
    DrawerController _drawerController = new DrawerController();
    PopupMenuController _menuController;
  
    static Style _style = new Style('''
      display: flex;
  