anchor.diff:      );
     }
   
  -  void _handleWheelEvent(
  -      html.Event e, void Function(Iterable<ui.PointerData>) sink) {
  +  void _handleWheelEvent(html.Event e) {
       assert(e is html.WheelEvent);
       final html.WheelEvent event = e as html.WheelEvent;
       if (_debugLogPointerEvents) {
  
positive.code:     }, acceptOutsideGlasspane: true);
  
      _addWheelEventListener((html.Event event) {
        _handleWheelEvent(event, _callback);
      });
    }
  
  
negative.code:     });
  
      _addWheelEventListener((html.Event event) {
        _handleWheelEvent(event);
      });
    }
  
  