test_current_month_and_year_is_selected failed on mako #76

On mako image #76 this test failed with:

Traceback (most recent call last):
  File "/home/phablet/autopilot/calendar_app/tests/test_dayview.py", line 34, in setUp
    self.main_view.get_day_view, Eventually(NotEquals(None)))
  File "/usr/lib/python3/dist-packages/testtools/testcase.py", line 404, in assertThat
    mismatch_error = self._matchHelper(matchee, matcher, message, verbose)
  File "/usr/lib/python3/dist-packages/testtools/testcase.py", line 454, in _matchHelper
    mismatch = matcher.match(matchee)
  File "/usr/lib/python3/dist-packages/autopilot/matchers/__init__.py", line 113, in match
    wait_fun(self.matcher, self.timeout)
  File "/usr/lib/python3/dist-packages/autopilot/matchers/__init__.py", line 129, in _callable_wait_for
    new_value = refresh_fn()
  File "/home/phablet/autopilot/calendar_app/emulators.py", line 33, in get_day_view
    return self.wait_select_single("DayView")
  File "/usr/lib/python3/dist-packages/autopilot/introspection/dbus.py", line 299, in wait_select_single
    return self.select_single(type_name, **kwargs)
  File "/usr/lib/python3/dist-packages/autopilot/introspection/dbus.py", line 248, in select_single
    raise StateNotFoundError(type_name_str, **kwargs)
autopilot.exceptions.StateNotFoundError: Object not found with name 'DayView'.

I was unable to reproduce this locally, despite running many times. This bug is primarily to track the status of this test in CI.