Bug 211710 [Regression] Data of cascading parameters in the report extended from the library can not be selected from the drop-down list when preview [01]
Description: Data of cascading parameters in the report extended from the library can not be selected from the drop-down list when preview. Build number: 2.2.2.v20071203-0630 Steps to reproduce: 1. New a Library with cascading parameters. 2. New a report and extend the cascading parameters from the library and preview. Expected result: Values can be selected from the drop-down list. Actual result: Values can not be selected from the drop-down list. Error log: N/A
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/impl/GetParameterDefinitionTask.java
{
			return Collections.EMPTY_LIST;
		}
		return this.getSelectionList( requestedParam.getName( ) );
	}
	public Collection getSelectionTreeForCascadingGroup(
			String parameterGroupName )
	{
		CascadingParameterGroupHandle parameterGroup = getCascadingParameterGroup( parameterGroupName );
		if ( parameterGroup == null )
			return Collections.EMPTY_LIST;
		SlotHandle parameters = parameterGroup.getParameters( );
		int parameterCount = parameters.getCount( );
		if ( DesignChoiceConstants.DATA_SET_MODE_SINGLE.equals( parameterGroup
				.getDataSetMode( ) ) )
		{
			
			IResultIterator resultIterator = getResultSetOfCascadingGroup( parameterGroup );
			if ( resultIterator == null )
			{
				return Collections.EMPTY_LIST;
			}
			Collection selectionTree = populateToSelectionTree( resultIterator,
					parameterGroup );
			close( resultIterator );
			return selectionTree;
		}
		else
		{
			ParameterHelper[] parameterHelpers = getParameterHelpers( parameterGroup );