anchor.diff:    // Size size = Size.zero;
     // In debug builds, however:
     Size _size = Size.zero;
  +
  +  /// The size of this render box computed during layout
  +  ///
  +  /// This value is stale whenever this object is marked as needing layout.
  +  /// During [performLayout], do not read the size of a child unless you pass
  +  /// true for parentUsesSize when calling the child's [layout] function.
  +  ///
  +  /// The size of a box should be set only during the box's [performLayout] or
  +  /// [performResize] functions. If you wish to change the size of a box outside
  +  /// of those functins, call [markNeedsLayout] instead to schedule a layout of
  +  /// the box.
     Size get size {
       if (_size is _DebugSize) {
         final _DebugSize _size = this._size; // TODO(ianh): Remove this once the analyzer is cleverer
  
positive.code:     _debugDoingBaseline = value;
      return true;
    }
    // getDistanceToBaseline() returns the distance from the
    // y-coordinate of the position of the box to the y-coordinate of
    // the first given baseline in the box's contents. This is used by
    // certain layout models to align adjacent boxes on a common
    // baseline, regardless of padding, font size differences, etc. If
    // there is no baseline, and the 'onlyReal' argument was not set to
    // true, then it returns the distance from the y-coordinate of the
    // position of the box to the y-coordinate of the bottom of the box,
    // i.e., the height of the box. Only call this after layout has been
    // performed. You are only allowed to call this from the parent of
    // this node during that parent's performLayout() or paint().
    double getDistanceToBaseline(TextBaseline baseline, { bool onlyReal: false }) {
      assert(!needsLayout);
      assert(!_debugDoingBaseline);
  
negative.code:     return _transformPoint(transform, point);
    }
  
    /// Convert the given point from the local coordiante system for this box to
    /// the global coordinate sytem
    Point localToGlobal(Point point) {
      List <RenderObject> renderers = <RenderObject>[];
      for (RenderObject renderer = this; renderer != null; renderer = renderer.parent)
  