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
int index = 0;
		for ( int i = 0; i < pagebreakAfterChoicesAll.length; i++ )
		{
			if ( pagebreakAfterChoicesAll[i].getName( ).equals( pageBreakAfter ) )
			{
				index = i;
				break;
			}
		}
		return index;
	}
	private int getPagebreakBeforeIndex( String pageBreakBefore )
	{
		int index = 0;
		for ( int i = 0; i < pagebreakBeforeChoicesAll.length; i++ )
		{
			if ( pagebreakBeforeChoicesAll[i].getName( )
					.equals( pageBreakBefore ) )
			{
				index = i;
				break;
			}
		}
		return index;
	}
	/**
	 * Sets the model input.
	 * 
	 * @param input
	 */