anchor.diff:  
     T _result;
   
  -  void handleStatusChanged(AnimationStatus status) {
  +  void _handleStatusChanged(AnimationStatus status) {
       switch (status) {
         case AnimationStatus.completed:
           if (overlayEntries.isNotEmpty)
  
positive.code:     });
    }
  
    BuildContext get subtreeContext => _subtreeKey.currentContext;
  
  
  
negative.code:   }
  
    void didPush() {
      _animation.addStatusListener(_handleStatusChanged);
      _controller.forward();
      super.didPush();
    }
  