      * @private
      * Helper method to test whether a component is visible to user.
      */ 
-    protected function componentIsVisible(component:UIComponent):Boolean
+    mx_internal function componentIsVisible(component:UIComponent):Boolean
     {
         return component && component.visible && 
             component.width && component.height && component.alpha;

     *  Helper method to add a UIComponent instance to either an IVisualElementContainer
     *  or DisplayObjectContainer. 
     */ 
    protected function addComponentToContainerAt(component:UIComponent, 
                                                 container:UIComponent, 
                                                 index:int):void
    {

     *  @private
     *  Helper method to set the child index of the given component.
     */ 
    mx_internal function setComponentChildIndex(component:UIComponent, 
                                              container:UIComponent, 
                                              index:int):void
    {
