Bug 152412 [Smoke]Insert,delete a master page, can not take effect
Insert,delete a master page, can not take effect Steps: 1.new a report 2.open outline view, insert a master page or delete a master page Actual Results 1.Can not take effect.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/editors/parts/event/ModelEventManager.java
/**
	 * Gets the visitor.
	 * 
	 * @return the visitor
	 */
	private ListenerElementVisitor getListenerElementVisitor( )
	{
		if ( visitor == null )
		{
			visitor = new ListenerElementVisitor( this );
		}
		return visitor;
	}
	/**Hook the command stack, to add the command stack listener to the stack.
	 * @param stack
	 */
	 
	
	 
	public void hookCommandStack( WrapperCommandStack stack )
	{
		stack.addCommandStackListener( commandStackListener );
	}
	/**Unhook the root.
	 * @param stack
	 */
	public void unhookCommandStack( WrapperCommandStack stack )
	{
		stack.removeCommandStackListener( commandStackListener );
	}