anchor.diff:      onHeightChanged();
     }
   
  -  void _sizesRecheck() {
  +  void _sizesRecheck(EventEmitter<ResizeEvent> emitter) {
       if (_changePending) return;
       _changePending = true;
       new Future.delayed(const Duration(milliseconds: 20)).then((_) {
         _changePending = false;
         width = sizeCheckedElement.offsetWidth;
         height = sizeCheckedElement.offsetHeight;
  +      emitter.add(this);
       });
     }
   }
  
positive.code: 
  /// Provide resize event on element
  /// Inspired by https://github.com/flowkey/resize-sensor
  /// Example usage:
  ///
  ///    @Component(
  ///       selector: 'my-component',
  ///       directives: const[ResizeSensor],
  ///       template: '''
  ///       <div #sizeCheckedElement>
  ///         some content
  ///         <resize-sensor [resizeEvent]="resizeEvent"></resize-sensor>
  ///       </div>
  ///    ''')
  ///    class MyComponent implements OnInit {
  ///      HtmlElement _sizeCheckedElement;
  ///      ResizeEvent resizeEvent = new ResizeEvent();
  ///      @ViewChild('sizeCheckedElement')
  ///      set sizeCheckedElement(ElementRef elementRef) {
  ///        _sizeCheckedElement = elementRef.nativeElement;
  ///      }
  ///
  ///      @override
  ///      void ngOnInit() {
  ///        resizeEvent.sizeCheckedElement = _sizeCheckedElement;
  ///        resizeEvent.onHeightChanged = (){
  ///          print(resizeEvent.height);
  ///        };
  ///        resizeEvent.onWidthChanged = (){
  ///          print(resizeEvent.height);
  ///        };
  ///      }
  ///    }
  @Component(
  
negative.code:   }
  
    void onScroll() {
      resizeEvent._sizesRecheck(resize);
      reset();
    }
  
    @override
  