Bug 139346 Using isTopN in table inside list group header doesn't work.
Description: Using isTopN in table inside list group header doesn't work. Steps to reproduce: 1.Insert a list with a group 2.Insert a table to list group header 3.Using Total.isTopN(row[],2,null,0) as filter expression in table item. 4.Preview Result: Only the first group displayed top 2 records, other groups kept display all records.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/QueryExecutor.java
protected 	IQuery					odiQuery;
	
	
	protected	IQueryService			outerResults;	
	private 	IResultIterator			odiResult;
	private 	IExecutorHelper			parentHelper;
	
	private List temporaryComputedColumns = new ArrayList();
	private static Logger logger = Logger.getLogger( DataEngineImpl.class.getName( ) );
	
	/**
	 * @param sharedScope
	 * @param baseQueryDefn
	 * @param aggrTable
	 */
	QueryExecutor( Scriptable sharedScope, IBaseQueryDefinition baseQueryDefn,
			AggregateTable aggrTable )
	{
		this.sharedScope = sharedScope;
		this.baseQueryDefn = baseQueryDefn;
		this.aggrTable = aggrTable;
	}
	
	/**
	 * Provide the actual DataSourceRuntime used for the query.
	 * 
	 * @return
	 */
	abstract protected DataSourceRuntime findDataSource( )
			throws DataException;