Created by: fkorotkov
At the moment enableObjcInterop flag was always try which can be simply achieved by having it in .buckconfig section or via swift_compilerf_flags.
Having this flag always on tides Swift compiler to always assume ObjC environment. See https://github.com/apple/swift/blob/bbecb33d13bf91696ea917f1b2a29f133168e67b/lib/Basic/LangOptions.cpp#L226-L229