cheets_ContainerMount failed on multiple boards (auron_yuna, bob, caroline, cyan, etc).

02/07 20:51:01.165 WARNI|               arc:0460| Iteration 1 failed, taking a screenshot.
02/07 20:51:01.417 WARNI|              test:0637| The test failed with the following exception
Traceback (most recent call last):
  File "/usr/local/autotest/common_lib/test.py", line 631, in _exec
    _call_test_function(self.execute, *p_args, **p_dargs)
  File "/usr/local/autotest/common_lib/test.py", line 831, in _call_test_function
    return func(*args, **dargs)
  File "/usr/local/autotest/common_lib/test.py", line 495, in execute
    dargs)
  File "/usr/local/autotest/common_lib/test.py", line 362, in _call_run_once_with_retry
    postprocess_profiled_run, args, dargs)
  File "/usr/local/autotest/common_lib/test.py", line 400, in _call_run_once
    self.run_once(*args, **dargs)
  File "/usr/local/autotest/tests/cheets_ContainerMount/cheets_ContainerMount.py", line 58, in run_once
    mountinfo.get_mountinfo_list(arc.get_obb_mounter_pid()))
  File "/usr/local/autotest/common_lib/cros/arc.py", line 276, in get_obb_mounter_pid
    return utils.system_output('pgrep -f -u root ^/usr/bin/arc-obb-mounter')
  File "/usr/local/autotest/common_lib/utils.py", line 1056, in system_output
    args=args).stdout
  File "/usr/local/autotest/common_lib/utils.py", line 748, in run
    "Command returned non-zero exit status")

Assigning to recent modifier of cheets_ContainerMount.py.
yusukes, could you route to the relevant person?