anchor.diff:      assert(rootNode != null);
       assert(rootNode._spriteBox == null);
   
  +    // Setup transform mode
  +    this.transformMode = mode;
  +
       // Setup root node
       this.rootNode = rootNode;
  -
  -    // Setup transform mode
  -    this.transformMode = mode;
     }
   
     void _removeSpriteBoxReference(Node node) {
  
positive.code:         rootNode.size = new Size(systemWidth, systemHeight);
          break;
        case SpriteBoxTransformMode.nativePoints:
          break;
        default:
          assert(false);
  
negative.code:     if (value == _rootNode) return;
  
      // Ensure that the root node has a size
      assert(_transformMode == SpriteBoxTransformMode.nativePoints
        || value.size.width > 0);
      assert(_transformMode == SpriteBoxTransformMode.nativePoints
        || value.size.height > 0);
  
      // Remove sprite box references
      if (_rootNode != null) _removeSpriteBoxReference(_rootNode);
  