Bug 176450 Support link to CSS Feature(Model Part)
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/command/ComplexPropertyCommand.java
*/
	public void insertItem( MemberRef ref, IStructure item, int posn )
			throws SemanticException
	{
		assert ref != null;
		if ( item == null )
			return;
		PropertyDefn propDefn = ref.getPropDefn( );
		assert propDefn != null;
		assertExtendedElement( module, element, propDefn );
		checkListMemberRef( ref );
		checkItem( ref, item );
		List list = ref.getList( module, element );
		element.checkStructureList( module, ref.getPropDefn( ), list, item );
		ActivityStack stack = getActivityStack( );
		stack.startTrans( ModelMessages
				.getMessage( MessageConstants.INSERT_ITEM_MESSAGE ) );
		makeLocalCompositeValue( ref );
		list = ref.getList( module, element );
		if ( null == list )
		{
			list = new ArrayList( );
			MemberRecord memberRecord = new MemberRecord( module, element, ref,
					list );
			stack.execute( memberRecord );
		}
		if ( posn < 0 || posn > list.size( ) )
			throw new IndexOutOfBoundsException(
					"Posn: " + posn + ", List Size: " + list.size( ) ); 
		MemberRef insertRef = new CachedMemberRef( ref, posn );