message: [lang/Objc] UNXFAIL a test. Nullability has been implemented in clang.
  (a while ago).
  <rdar://problem/20416388>
diff: @@ -23,7 +23,6 @@ class IncompleteModulesTestCase(TestBase):
  self.line = line_number('main.m', '// Set breakpoint 0 here.')
  @skipUnlessDarwin
  - @unittest2.expectedFailure("rdar://20416388")
  @skipIf(macos_version=["<", "10.12"], debug_info=no_match(["gmodules"]))
  def test_expr(self):
  self.build()
  