These tests require the ObjC Foundation framework currently (although it
should be possible have them use the swift corelibs Foundation project
to satisfy this requirement). Marking the tests indicates that these
tests do not have the dependencies to run on Windows.
Fixes rdar://problem/19924834, which exposes a case where delayed protocols cause an imported enum's Equatabe protocol conformance to get instantiated too late, if the enum is imported by one file that doesn't use the Equatable conformance, and a subsequent file in the same invocation then uses the conformance. Jordan notes that delaying these conformances is no longer desirable, now that we dynamically detect conformances.
Swift SVN r25741