method.c (make_thunk): Use overload machinery to make name.

method.c (make_thunk): Use overload machinery to make name.

	* method.c (make_thunk): Use overload machinery to make name.
	* search.c (covariant_return_p): New fn.
	(get_matching_virtual): Use it.
	* init.c (build_new_1): Fix check for void.

From-SVN: r20215