Bug 136027 [Smoke]the report with a gounp can not preview
Description: the report with a gounp can not preview Steps to reproduce: 1. new a datasource and a dataset 2. drag the dataset to the layout 3. Add a group on the table. save and preview. Actual result: "Error happened while running the report" is appeared.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/GroupDialog.java
else
					{
						inputGroup.clearContents( GroupHandle.FOOTER_SLOT );
					}
				}
			}
			if ( ascending.getSelection( ) )
			{
				inputGroup.setSortDirection( DesignChoiceConstants.SORT_DIRECTION_ASC );
			}
			else
			{
				inputGroup.setSortDirection( DesignChoiceConstants.SORT_DIRECTION_DESC );
			}
			inputGroup.setPageBreakBefore( pagebreakBeforeChoicesAll[pagebreakBeforeCombo.getSelectionIndex( )].getName( ) );
			inputGroup.setPageBreakAfter( pagebreakAfterChoicesAll[pagebreakAfterCombo.getSelectionIndex( )].getName( ) );
			inputGroup.setRepeatHeader( repeatHeaderButton.getSelection( ) );
		}
		catch ( SemanticException e )
		{
			ExceptionHandler.handle( e );
			return;
		}
		setResult( inputGroup );
		super.okPressed( );
	}
	/**
	 * Returns the internal type index by its value.
	 * 
	 * @param interval