 import mx.core.IFactory;
 import mx.core.mx_internal;
 import mx.events.PropertyChangeEvent;
-import mx.managers.IFocusManagerComponent;
 
 import spark.components.gridClasses.GridColumn;
 import spark.components.gridClasses.GridColumnHeaderGroupLayout;

     *  
     *  @langversion 3.0
     *  @playerversion Flash 10
     *  @playerversion AIR 1.5
     *  @productversion Flex 4
     */
    public function GridColumnHeaderGroup()
    {

     *  @playerversion AIR 2.0
     *  @productversion Flex 4.5
     */    
    protected function gchg_mouseMoveHandler(event:MouseEvent):void
    {
        const eventStageXY:Point = new Point(event.stageX, event.stageY);
        const eventHeaderGroupXY:Point = globalToLocal(eventStageXY);
