Bug 167545 Copy a cascading parameter group and paste it to another parameter group causes an exception thrown
Steps to reproduce: 1.Copy a cascading parameter group using short cut key "Ctrl+x"/"Ctrl+c", or choosing context menu "Cut"/"Copy"; 2.Paste it to another parameter group using short cut key "Ctrl+v", or choosing context menu "Paste"; Expected result: The source one is pasted in the destination. Actual result: An exception thrown org.eclipse.birt.report.model.api.command.ContentException: The Cascading Parameter Group("Source") is not allowed in the slot (parameters) of Parameter Group("Destination").
UI/org.eclipse.birt.report.designer.core/src/org/eclipse/birt/report/designer/util/DEUtil.java
{
		if ( model instanceof ParameterHandle )
		{
			return ExpressionUtil.createJSParameterExpression( ( (ParameterHandle) model ).getQualifiedName( ) );
		}
		if ( model instanceof DataSetItemModel )
		{
			String colName = ( (DataSetItemModel) model ).getAlias( );
			if ( colName == null || colName.trim( ).length( ) == 0 )
			{
				colName = ( (DataSetItemModel) model ).getName( );
			}
			return getColumnExpression( colName );
		}
		if ( model instanceof ComputedColumnHandle )
		{
			return getColumnExpression( ( (ComputedColumnHandle) model ).getName( ) );
		}
		if ( model instanceof ResultSetColumnHandle )
		{
			return getResultSetColumnExpression( ( (ResultSetColumnHandle) model ).getColumnName( ) );
		}
		if ( model instanceof DataSetParameterHandle )
		{
			return IReportElementConstants.STOREDPROCUDURE_OUTPUT_PREFIX
					+ "[\"" + escape( ( (DataSetParameterHandle) model ).getName( ) ) + "\"]"; 
		}
		return null;
	}
	/**