Don't move object to the new class if it's already a descendant
Don't move object to the new class if it's already a descendant

If linked object belongs to a class which is a descendant of selected device type, then it's not necessary to change it's class.
sergejey/majordomo,sergejey/majordomo,tarasfrompir/majordomo,sergejey/majordomo,sergejey/majordomo,tarasfrompir/majordomo,tarasfrompir/majordomo,tarasfrompir/majordomo,sergejey/majordomo