Bug 103291 Group key doesn't support inputting text
Description: Group key doesn't support inputting text Steps to reproduce: 1.Add a table and bind it with data set 2.Add a group to the table: enter a row name in the "Group On:" textbox 3.Save and preview Expected result: Everything is OK Actual result: Error occurs because the group key is added as a string not a expression
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/GroupDialog.java
slotHandle.add( dataItemHandle );
				}
			}
			index = intervalType.getSelectionIndex( );
			inputGroup.setInterval( intervalChoices[index].getName( ) );
			if ( index != 0 )
			{
				inputGroup.setIntervalRange( intervalRange.getSelection( ) );
			}
			if ( inputGroup instanceof TableGroupHandle )
			{
				if ( includeHeader.getSelection( ) != inputGroup.hasHeader( ) )
				{
					if ( includeHeader.getSelection( ) )
					{
						inputGroup.getHeader( ).add( createRow( ) );
					}
					else
					{
						inputGroup.clearContents( GroupHandle.HEADER_SLOT );
					}
				}
				if ( includeFooter.getSelection( ) != inputGroup.hasFooter( ) )
				{
					if ( includeFooter.getSelection( ) )
					{
						inputGroup.getFooter( ).add( createRow( ) );
					}
					else
					{