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/data/dte/ReportQueryBuilder.java
{
				query.getSorts( )
						.addAll( createSorts( (ListingDesign) item ) );
				query.getFilters( )
						.addAll( createFilters( (ListingDesign) item ) );
			}
			else if ( item instanceof ExtendedItemDesign )
			{
				query.getFilters( ).addAll(
						createFilters( (ExtendedItemDesign) item ) );
			}
		}
		/**
		 * get Localized string by the resouce key and <code>Locale</code>
		 * object in <code>context</code>
		 * 
		 * @param resourceKey
		 *            the resource key
		 * @param text
		 *            the default value
		 * @return the localized string if it is defined in report deign, else
		 *         return the default value
		 */
		protected String getLocalizedString( String resourceKey, String text )
		{
			if ( resourceKey == null )
			{
				return text;
			}
			String ret = report.getReportDesign( ).getMessage( resourceKey,