The following test failed on a pre-CQ run which runs fine locally and seems totally unrelated to the change:
test_schedule_running_host_queue_entries_fail (autotest_lib.scheduler.monitor_db_unittest.JobSchedulingTest
 
https://chromium-review.googlesource.com/909710
https://luci-milo.appspot.com/buildbot/chromiumos.tryserver/pre_cq/82022
https://logs.chromium.org/v/?s=chromeos%2Fbb%2Fchromiumos.tryserver%2Fpre_cq%2F82021%2F%2B%2Frecipes%2Fsteps%2FUnitTest%2F0%2Fstdout

autotest-0.0.2-r9098: ======================================================================
autotest-0.0.2-r9098: FAIL: test_schedule_running_host_queue_entries_fail (autotest_lib.scheduler.monitor_db_unittest.JobSchedulingTest)
autotest-0.0.2-r9098: ----------------------------------------------------------------------
autotest-0.0.2-r9098: Traceback (most recent call last):
autotest-0.0.2-r9098:   File "/build/moblab-generic-vm/tmp/portage/chromeos-base/autotest-0.0.2-r9098/work/autotest-0.0.2/scheduler/monitor_db_unittest.py", line 822, in test_schedule_running_host_queue_entries_fail
autotest-0.0.2-r9098:     self._dispatcher._schedule_running_host_queue_entries)
autotest-0.0.2-r9098: AssertionError: SchedulerError not raised
autotest-0.0.2-r9098: 
autotest-0.0.2-r9098: ----------------------------------------------------------------------
autotest-0.0.2-r9098: Ran 42 tests in 18.150s
autotest-0.0.2-r9098: 
autotest-0.0.2-r9098: FAILED (failures=1)
autotest-0.0.2-r9098: Traceback (most recent call last):
autotest-0.0.2-r9098:   File "./utils/unittest_suite.py", line 294, in <module>
autotest-0.0.2-r9098:     main()
autotest-0.0.2-r9098:   File "./utils/unittest_suite.py", line 281, in main
autotest-0.0.2-r9098:     errors = find_and_run_tests(absolute_start, options)
autotest-0.0.2-r9098:   File "./utils/unittest_suite.py", line 264, in find_and_run_tests
autotest-0.0.2-r9098:     pe.run_until_completion()
autotest-0.0.2-r9098:   File "/build/moblab-generic-vm/tmp/portage/chromeos-base/autotest-0.0.2-r9098/work/autotest-0.0.2/utils/parallel.py", line 67, in run_until_completion
autotest-0.0.2-r9098:     self._run(self.ready_to_run.pop())
autotest-0.0.2-r9098:   File "/build/moblab-generic-vm/tmp/portage/chromeos-base/autotest-0.0.2-r9098/work/autotest-0.0.2/utils/parallel.py", line 53, in _run
autotest-0.0.2-r9098:     function()
autotest-0.0.2-r9098:   File "./utils/unittest_suite.py", line 254, in <lambda>
autotest-0.0.2-r9098:     run_module = lambda module=module_names: run_test(module, options)
autotest-0.0.2-r9098:   File "./utils/unittest_suite.py", line 159, in run_test
autotest-0.0.2-r9098:     raise TestFailure(msg)
autotest-0.0.2-r9098: __main__.TestFailure: autotest_lib.scheduler.monitor_db_unittest had 1 failures and 0 errors.