The hash of enum values are different from that of their underlying
rawValue due to the implementation details of Int on 64-bit platform
which are not true on 32-bit platforms. This commit removes the tests
that rely on this behavior.
rdar://138032645
* [cxx-interop] Add Hashable conformance to imported enums
Previously, imported enums only conformed to RawRepresentable and Equatable,
so they could not be used as members of a Set or keys of a Dictionary.
This patch adds Hashable conformance to give them that ability,
as well as some test cases to clarify the expected behavior.
Existing test cases are updated to reflect this new conformance.
rdar://129713687
