Bug 189706 Enhance computed column aggregation function handling in UI.
Due to the issue discussed in 189705, current computed column aggregation builder in data set editor has bugs to extend: 1.When new a computed column, the aggregation argument field cannot be correctly set. 2.The argument field cannot be correct grayed out when user select a aggregation function without arguments 3.The available aggregation function list is incomprehensive 4.Some aggregation function cannot be set to model(say, weightedAve).
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/executor/transform/pass/DataSetProcessUtil.java
iccState,
				computedColumnHelper,
				filterByRow,
				psController,
				session );
		instance.populateDataSet( );
	}
	
	/**
	 * 
	 * @throws DataException
	 */
	private void populateDataSet() throws DataException
	{
		int originalMaxRows = this.populator.getQuery( ).getMaxRows( );
		
		boolean changeMaxRows = filterByRow == null?false:filterByRow.getFilterList( FilterByRow.QUERY_FILTER )
			.size( )
			+ filterByRow.getFilterList( FilterByRow.GROUP_FILTER ).size( ) > 0;
		if ( changeMaxRows )
			this.populator.getQuery( ).setMaxRows( 0 );
			
		List aggCCList = prepareComputedColumns(TransformationConstants.DATA_SET_MODEL );
		doDataSetFilter( changeMaxRows );
		populateAggrCCs( this.getAggrComputedColumns( aggCCList, true ));
		
		
		
		populateComputedColumns( this.getAggrComputedColumns( aggCCList, false ));