anchor.diff:  
   class Label extends Skinnable {
   
  +  Layout _layout;
     String _description;
     String _text;
     HorizontalAlign _hAlign;
  
positive.code:     if (content != null) {
        addChild(content);
      }
      new SingleLayout(horizontalAlign: hAlign, verticalAlign: vAlign).order(this);
      validate();
    }
  
  
negative.code:         addChild(content);
        }
      }
      _layout.order(this);
    }
  
    @override
  