Bug 154828 Item from library contant user properties can't delete
Details: Item from library contant user properties can't delete Step: 1.New a library. 2.Add a label and add a user properites. 3.Public the library. 4.New a report design and use the library 5.Drop the label from library explorer into layout. 6.Try to delete it. Actual result: The label from library contant user properties can't be delete. Exception reuslt: The label can be delete.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/command/ContentCommand.java
ContentException.DESIGN_EXCEPTION_RECURSIVE );
		
		if ( !element.getDefn( ).isContainer( ) )
			throw new ContentException( element, fromSlotID,
					ContentException.DESIGN_EXCEPTION_NOT_CONTAINER );
		if ( !to.getDefn( ).isContainer( ) )
			throw new ContentException( to, toSlotID,
					ContentException.DESIGN_EXCEPTION_NOT_CONTAINER );
		ContainerSlot fromSlot = element.getSlot( fromSlotID );
		if ( fromSlot == null )
			throw new ContentException( element, fromSlotID,
					ContentException.DESIGN_EXCEPTION_SLOT_NOT_FOUND );
		ContainerSlot toSlot = to.getSlot( toSlotID );
		if ( toSlot == null )
			throw new ContentException( to, toSlotID,
					ContentException.DESIGN_EXCEPTION_SLOT_NOT_FOUND );
		if ( !fromSlot.contains( content ) )
			throw new ContentException( element, fromSlotID, content,
					ContentException.DESIGN_EXCEPTION_CONTENT_NOT_FOUND );
		if ( !fromSlot.canDrop( content ) )
			throw new ContentException( element, fromSlotID, content,
					ContentException.DESIGN_EXCEPTION_DROP_FORBIDDEN );
		
		
		if ( hasDescendents( content, fromSlotID ) )
		{
			throw new ContentException( element, fromSlotID,
					ContentException.DESIGN_EXCEPTION_HAS_DESCENDENTS );
		}
		SlotDefn slotInfo = (SlotDefn) to.getDefn( ).getSlot( toSlotID );