swift234

Switch ClassDecl::getSuperclass() and EnumDecl::getRawType() to interface types.

This has the nice "side effect" of making overrides of generic
functions work better, fixing the remaining type checker issues from
<rdar://problem/15836098>.

Also synthesize the types for derived RawRepresentable conformances
directly rather than going through the type checker, so we get the
interface types right. 



Swift SVN r14066