Bug 189534 Computed Column aggregation builder doesn't accept argument.
The aggregation builder of computed column should be enhanced so that 1. It can accept aggregation argument. 2. Only when the selected computed column can accept argument should the argument dialog enabled.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/executor/transform/pass/DataSetProcessUtil.java
false,
						this.session );
			AggregationHelper helper = new AggregationHelper( new AggrDefnManager( aggrInfos ),
					this.populator );
			AggrComputedColumnHelper ccHelper = new AggrComputedColumnHelper( helper,
					aggrNames );
			this.populator.getQuery( ).getFetchEvents( ).add( 0, ccHelper );
			PassUtil.pass( populator,
					new OdiResultSetWrapper( populator.getResultIterator( ) ),
					false,
					this.session );
			this.populator.getQuery( ).getFetchEvents( ).remove( 0 );
		}
		finally
		{
			Context.exit( );
		}
	}
	/**
	 * 
	 * @throws DataException
	 */
	private void doDataSetFilter( boolean changeMaxRows ) throws DataException
	{
		if(	!psController.needDoOperation( PassStatusController.DATA_SET_FILTERING ))
			return;
				
		
		applyFilters( FilterByRow.DATASET_FILTER,
				changeMaxRows );