Bug 192789 Support to render reportlet using bookmark in frameset servlet.
Description: Support to render reportlet using bookmark in frameset servlet. At present, only run and preview servlet support __isreportlet&__bookmark to generate reportlet.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/service/BirtViewerReportService.java
public Collection getSelectionListForCascadingGroup(
			IViewerReportDesignHandle design, String groupName,
			Object[] groupKeys, InputOptions options )
			throws ReportServiceException
	{
		IGetParameterDefinitionTask task = null;
		HttpServletRequest request = (HttpServletRequest) options
				.getOption( InputOptions.OPT_REQUEST );
		try
		{
			task = getParameterDefinitionTask( design, options );
			if ( task != null )
			{
				ViewerAttributeBean bean = getViewerAttrBean( options );
				if ( bean != null )
				{
					task.setLocale( bean.getLocale( ) );
					task.setParameterValues( bean.getParameters( ) );
				}
				
				BirtUtility.addTask( request, task );
				task.evaluateQuery( groupName );
				Collection selectionList = task
						.getSelectionListForCascadingGroup( groupName,
								groupKeys );
				return convertEngineParameterSelectionChoice( selectionList );
			}
		}
		finally
		{