Map a list of type parameter symbols to skolemized symbols, which can be deskolemized to the original type parameter.
Map a list of type parameter symbols to skolemized symbols, which can be deskolemized to the original type parameter. (A skolem is a representation of a bound variable when viewed inside its scope.) !!!Adriaan: this does not work for hk types.
Convert to corresponding type parameters all skolems of method
parameters which appear in tparams.
The name of this trait defines the eventual intent better than it does the initial contents.