Bug 198504 The same name aggregation should be hint in dialog[0001]
Description: The same name aggregation should be hint in dialog[0001] Step: 1.New a datasource, dataset, table and binding the dataset. 2.New a aggregation column binding on table named aggr1. 3.Drop a aggregation item into table and set the named as aggr1. 4.Click OK Actual result: Pop up an error message said that the name is exist. Expected result: It can hint in dialog when input the same name, but pop up an error dialog
xtab/org.eclipse.birt.report.item.crosstab.ui/src/org/eclipse/birt/report/item/crosstab/internal/ui/dialogs/CrosstabBindingDialogHelper.java
{
		try
		{
			CrosstabReportItemHandle xtabHandle = (CrosstabReportItemHandle) ( (ExtendedItemHandle) getBindingHolder( ) ).getReportItem( );
			String[] aggOns = getAggOns( xtabHandle );
			cmbAggOn.setItems( aggOns );
			String aggstr = "";
			if ( getBinding( ) != null )
			{
				List aggOnList = getBinding( ).getAggregateOnList( );
				int i = 0;
				for ( Iterator iterator = aggOnList.iterator( ); iterator.hasNext( ); )
				{
					if ( i > 0 )
						aggstr += ",";
					String name = (String) iterator.next( );
					aggstr += name;
					i++;
				}
			}
			else if ( getDataItemContainer( ) instanceof AggregationCellHandle )
			{
				AggregationCellHandle cellHandle = (AggregationCellHandle) getDataItemContainer( );
				if ( cellHandle.getAggregationOnRow( ) != null )
				{
					aggstr += cellHandle.getAggregationOnRow( )
							.getFullName( );
					if ( cellHandle.getAggregationOnColumn( ) != null )
					{
						aggstr += ",";