anchor.diff:      if (oldNode != null)
         oldNode._defunct = true;
   
  -    assert(node._root is RenderCSS);
  +    assert(node.root is RenderCSS);
       return node;
     }
   }
  
positive.code:     _trace('_sync($outString) $key');
    }
  
    void _removeChild(UINode node) {
      _traceSync(_SyncOperation.REMOVAL, node._key);
      node._remove();
    }
  
negative.code:     inlineStyle: inlineStyle
    );
  
    void syncRenderNode(UINode old) {
      super.syncRenderNode(old);
      root.direction = direction;
    }
  }
  
  class FillStackContainer extends OneChildListRenderNodeWrapper {
  
    RenderCSSStack root;
    RenderCSSStack createNode() => new RenderCSSStack(this);
  
    static final FillStackContainer _emptyContainer = new FillStackContainer();
  
    RenderNodeWrapper get emptyNode => _emptyContainer;
  
    FillStackContainer({
      Object key,
  