job_aborter on cros-full-0033.mtv is stuck in a crash loop:
    chromeos-test@cros-full-0033:/usr/local/autotest$ status job_aborter ; sleep 5 ; status job_aborter
    job_aborter start/running, process 235485
    job_aborter start/post-stop, process 236357

Initially, the error prompting the crash looked like this:
job_aborter: 2018-08-31 07:41:24,908:DEBUG:job_aborter:_main_loop:66:Tick
Traceback (most recent call last):
  File "/usr/lib/python2.7/runpy.py", line 162, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "/usr/lib/python2.7/runpy.py", line 72, in _run_code
    exec code in run_globals
  File "/usr/local/autotest/venv/lucifer/cmd/job_aborter.py", line 203, in <module>
    main(sys.argv[1:])
  File "/usr/local/autotest/venv/lucifer/cmd/job_aborter.py", line 51, in main
    _main_loop(jobdir=args.jobdir)
  File "/usr/local/autotest/venv/lucifer/cmd/job_aborter.py", line 68, in _main_loop
    _main_loop_body(metrics, jobdir)
  File "/usr/local/autotest/venv/lucifer/cmd/job_aborter.py", line 75, in _main_loop_body
    lease.id: lease for lease in leasing.leases_iter(jobdir)
  File "/usr/local/autotest/venv/lucifer/cmd/job_aborter.py", line 76, in <dictcomp>
    if not lease.expired()
  File "/usr/local/autotest/venv/lucifer/leasing.py", line 96, in expired
    return not _fcntl_locked(self._entry.path)
  File "/usr/local/autotest/venv/lucifer/leasing.py", line 157, in _fcntl_locked
    fd = os.open(path, os.O_WRONLY)
OSError: [Errno 13] Permission denied: '/usr/local/autotest/leases/232343460'

That file was a bit odd:
    chromeos-test@cros-full-0033:~$ ls -l /usr/local/autotest/leases/232343460
    -rw-r--r-- 1 chromeos-hwtest-corp-role primarygroup 98561 Aug 30 10:05 /usr/local/autotest/leases/232343460
    chromeos-test@cros-full-0033:~$ file /usr/local/autotest/leases/232343460
    /usr/local/autotest/leases/232343460: Git index, version 2, 934 entries

I moved the file to /usr/local/autotest/tmp/232343460.  Afterward,
the failures started looking like this:
job_aborter: 2018-08-31 09:38:27,870:DEBUG:job_aborter:_main_loop:66:Tick
Traceback (most recent call last):
  File "/usr/lib/python2.7/runpy.py", line 162, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "/usr/lib/python2.7/runpy.py", line 72, in _run_code
    exec code in run_globals
  File "/usr/local/autotest/venv/lucifer/cmd/job_aborter.py", line 203, in <module>
    main(sys.argv[1:])
  File "/usr/local/autotest/venv/lucifer/cmd/job_aborter.py", line 51, in main
    _main_loop(jobdir=args.jobdir)
  File "/usr/local/autotest/venv/lucifer/cmd/job_aborter.py", line 68, in _main_loop
    _main_loop_body(metrics, jobdir)
  File "/usr/local/autotest/venv/lucifer/cmd/job_aborter.py", line 75, in _main_loop_body
    lease.id: lease for lease in leasing.leases_iter(jobdir)
  File "/usr/local/autotest/venv/lucifer/cmd/job_aborter.py", line 76, in <dictcomp>
    if not lease.expired()
  File "/usr/local/autotest/venv/lucifer/leasing.py", line 96, in expired
    return not _fcntl_locked(self._entry.path)
  File "/usr/local/autotest/venv/lucifer/leasing.py", line 157, in _fcntl_locked
    fd = os.open(path, os.O_WRONLY)
OSError: [Errno 6] No such device or address: '/usr/local/autotest/leases/232335143'

So...
    chromeos-test@cros-full-0033:/usr/local/autotest$ ls -l /usr/local/autotest/leases/232335143
    srwxr-xr-x 2 chromeos-test eng 0 Aug 31 09:39 /usr/local/autotest/leases/232335143

Which looks more normal for the leases content.  And therefore:
    chromeos-test@cros-full-0033:/usr/local/autotest$ rm /usr/local/autotest/leases/232335143

Now, maybe, it's getting better.  Certainly, it hasn't failed for
the past minute or two.

We need to do two things:
  * Explain what happened here.
  * Change job_aborter to ignore or purge problem content of this sort.