Most tests were using %swift or similar substitutions, which did not
include the target triple and SDK. The driver was defaulting to the
host OS. Thus, we could not run the tests when the standard library was
not built for OS X.
Swift SVN r24504
Though the value may be statically known in some cases, that isn't good enough to do what we try to do with this information. In particular, if we invoke a class method on a MetatypeConversion, we want to dispatch to the method of the original metatype, not statically call the method of the converted type, which is what is evident in the AST. Fixes rdar://problem/18877135.
Swift SVN r23277