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
eventHandler.setExecutorHelper( helper );
		
		
		odiResult = executeOdiQuery( eventHandler );
		
		
		helper.setJSRowObject( this.dataSet.getJSResultRowObject( ) );
		
		resetComputedColumns();
		
		this.dataSet.setResultSet( odiResult, false );
			
	    
	    aggregates = new AggregateCalculator( this.aggrTable, odiResult );
		    
	    
	    aggregates.calculate( getQueryScope() );
		
		this.isExecuted = true;
		
		logger.logp( Level.FINER,
				QueryExecutor.class.getName( ),
				"execute",
				"Finish executing" );
	}
	
	private void resetComputedColumns() {
		List l = this.getDataSet().getComputedColumns();
		if( l!= null)
			l.removeAll( this.temporaryComputedColumns );