message: This test is passing everywhere I can see, so I'm removing the xfail,
  to test that proposition.
  <rdar://problem/30100284>
diff: @@ -18,7 +18,6 @@ class ExitDuringStepTestCase(TestBase):
  mydir = TestBase.compute_mydir(__file__)
  @skipIfFreeBSD # llvm.org/pr21411: test is hanging
  - @expectedFailureAll(compiler="clang", bugnumber="rdar://problem/30100284")
  def test(self):
  """Test thread exit during step handling."""
  self.build(dictionary=self.getBuildFlags())
  @@ -28,7 +27,6 @@ class ExitDuringStepTestCase(TestBase):
  True)
  @skipIfFreeBSD # llvm.org/pr21411: test is hanging
  - @expectedFailureAll(compiler="clang", bugnumber="rdar://problem/30100284")
  def test_step_over(self):
  """Test thread exit during step-over handling."""
  self.build(dictionary=self.getBuildFlags())
  @@ -38,7 +36,6 @@ class ExitDuringStepTestCase(TestBase):
  False)
  @skipIfFreeBSD # llvm.org/pr21411: test is hanging
  - @expectedFailureAll(compiler="clang", bugnumber="rdar://problem/30100284")
  def test_step_in(self):
  """Test thread exit during step-in handling."""
  self.build(dictionary=self.getBuildFlags())
  