Bug 177504 Engine doesn't provide SubQuery for extended item
Engine doesn't provide SubQuery for extended item, so chart can't use container's binding to execute the query. If possible, engine could provide an option for extended item to choose whether engine could create the query, so extended item won't create SubQuery by itself.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/presentation/LocalizedContentVisitor.java
}
	/**
	 * handle the label.
	 * 
	 * @param label
	 *            label content
	 */
	public Object visitLabel( ILabelContent label, Object value )
	{
		handleOnRender( label );
		processLabel( label );
		return label;
	}
	/**
	 * process the label content
	 * 
	 * <li> localize the help text
	 * <li> localize the label content
	 * <li> handle it as it is an text
	 * 
	 * @param label
	 *            label object
	 */
	protected void processLabel( ILabelContent label )
	{
		String helpText = localize( label, label.getHelpKey( ), label.getHelpText( ) );
		label.setHelpText( helpText );
		
		if ( label.getText( ) == null )