Moves CDOs aside to immutable versions of classes(REINST_) so that the CDO's can safely be GC'd. TheseREINST_ classes will be re-parented to a native parent that we know will not be churning through this function again later, so we avoid O(N^2) processing of REINST classes. Maps each givenSKEL_ class to its appropriateREINST_ version of itself