anchor.diff:    //---------------------------------
     
     Completer _animationFrameCompleter;
  +  Future _animationFrameFuture;
     
     Future get animationFrame {
  -    if (_animationFrameCompleter != null) return _animationFrameCompleter.future;
  +    if (_animationFrameCompleter != null) return _animationFrameFuture;
       
       _animationFrameCompleter = new Completer();
       
  
positive.code: 
        ownerMap.add(invokation);
        
        animationFrame.then(
            (_) {
              ownerMap.remove(invokation);
              
  
negative.code:       (window.performance != null) &&
        (window.performance.now != null)
      ) return window.performance.now();
      return 10.0;
    }
    
    void scheduleMethod(dynamic owner, Function method, List arguments, {bool forceSingleExecution: false}) {
  