message: TestAppleSimulatorOSType: Pass the --standalone argument to simctl
  It looks like running without this argument was supported
  for legacy reasons, but a Xcode 11 beta made the argument
  mandatory for our usecase.
diff: @@ -46,7 +46,7 @@ class TestAppleSimulatorOSType(gdbremote_testcase.GdbRemoteTestCaseBase):
  self.build(dictionary={ 'EXE': exe_name, 'SDKROOT': sdkroot.strip(),
  'ARCH': arch })
  exe_path = self.getBuildArtifact(exe_name)
  - sim_launcher = subprocess.Popen(['xcrun', 'simctl', 'spawn',
  + sim_launcher = subprocess.Popen(['xcrun', 'simctl', 'spawn', '-s',
  deviceUDID, exe_path,
  'print-pid', 'sleep:10'],
  stderr=subprocess.PIPE)
  