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
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/dialogs/BindingDialogHelper.java
gridData = new GridData( GridData.FILL_HORIZONTAL
				| GridData.GRAB_HORIZONTAL );
		gridData.horizontalSpan = 2;
		aggOnComposite.setLayoutData( gridData );
		layout = new GridLayout( );
		layout.horizontalSpacing = layout.verticalSpacing = 0;
		layout.marginWidth = layout.marginHeight = 0;
		layout.numColumns = 2;
		aggOnComposite.setLayout( layout );
		btnTable = new Button( aggOnComposite, SWT.RADIO );
		btnTable.setText( getBindingHolder( ) instanceof TableHandle ? TABLE
				: LIST );
		btnTable.addSelectionListener( new SelectionListener( ) {
			public void widgetDefaultSelected( SelectionEvent e )
			{
			}
			public void widgetSelected( SelectionEvent e )
			{
				cmbGroup.setEnabled( false );
			}
		} );
		WidgetUtil.createGridPlaceholder( aggOnComposite, 1, false );
		btnGroup = new Button( aggOnComposite, SWT.RADIO );
		btnGroup.setText( GROUP );
		btnGroup.addSelectionListener( new SelectionListener( ) {
			public void widgetDefaultSelected( SelectionEvent e )
			{
			}
			public void widgetSelected( SelectionEvent e )
			{