message: [test] Disable TestConcurrentManySignals on Darwin.
  This test is flaky on GreenDragon. Disable it until we figure out why.
diff: @@ -14,6 +14,8 @@ class ConcurrentManySignals(ConcurrentEventsBase):
  # Atomic sequences are not supported yet for MIPS in LLDB.
  @skipIf(triple='^mips')
  + # This test is flaky on Darwin.
  + @skipIfDarwin
  def test(self):
  """Test 100 signals from 100 threads."""
  self.build(dictionary=self.getBuildFlags())
  