             const itemRenderer:IVisualElement = getVisibleItemRenderer(rowIndex, columnIndex);
             const bubbles:Boolean = mouseEvent.bubbles;
             const cancelable:Boolean = mouseEvent.cancelable;
+            const relatedObject:InteractiveObject = mouseEvent.relatedObject;
             const ctrlKey:Boolean = mouseEvent.ctrlKey;
             const altKey:Boolean = mouseEvent.altKey;
             const shiftKey:Boolean = mouseEvent.shiftKey;


package spark.components
{
    import flash.events.Event;
    import flash.events.MouseEvent;
    import flash.geom.Point;

                super.invalidateSize();
        }
        
        /**
         *  @private
         *  During virtual layout updateDisplayList() eagerly validates lazily
         *  created (or recycled) IRs.  Calls to invalidateDisplayList() eventually
         *  short-circuit but doing so early saves a few percent.
         */
        override public function invalidateDisplayList():void
        {
            if (!inUpdateDisplayList)
                super.invalidateDisplayList();
        }

        /**
         *  @private
         */
