test_outgoing_answer_remote_hangup failed on mako #108

This test is failing on mako image #108 with the following error:

Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/dialer_app/tests/test_calls.py", line 123, in test_outgoing_answer_remote_hangup
    elapsed_time = self.main_view.live_call_page.get_elapsed_call_time()
  File "/usr/lib/python2.7/dist-packages/dialer_app/emulators.py", line 46, in get_elapsed_call_time
    return self.wait_select_single(objectName='stopWatch').elapsed
  File "/usr/lib/python2.7/dist-packages/autopilot/introspection/dbus.py", line 520, in __getattr__
    self.refresh_state()
  File "/usr/lib/python2.7/dist-packages/autopilot/introspection/dbus.py", line 474, in refresh_state
    _, new_state = self.get_new_state()
  File "/usr/lib/python2.7/dist-packages/autopilot/introspection/dbus.py", line 564, in get_new_state
    raise StateNotFoundError(self.__class__.__name__, id=self.id)
StateNotFoundError: Object not found with name 'StopWatch' and properties {'id': 33}.

This can be reproduced locally but only happens once every 2-3 runs, maybe less frequently. Running the test in a loop 10 times should produce at least a couple of failures.