     
     /**
      *  The layout object for this container.  
-     *  This object determines how the visual elements are laid out in the container.
+     *  This object is responsible for the measurement and layout of 
+     *  the visual elements in the container.
      */
     public function get layout():LayoutBase
     {

     * 
     *  @param e The element that has changed size.
     */
    public function elementSizeChanged(e:IGraphicElement):void
    {
        // TODO!!! Optimize
        // Call super so that we don't invalidate the layout

    }
        
    /**
     *  @private
     * 
     *  Three properties are delegated to the layout: clipContent,
     *  verticalScrollPosition, horizontalScrollPosition.
     *  If the layout is reset, we copy the properties from the old
     *  layout to the new one.   If the new layout is null, then we
     *  temporarily store the delegated properties in _layoutProperties. 
     */
    public function set layout(value:LayoutBase):void
    {
