Not sure if I'm looking correctly, but it looks like on this test run (video_WebRtcMediaRecorder)

https://stainless.corp.google.com/browse/chromeos-autotest-results/267325746-chromeos-test/

the test was interrupted because the system applied an update and rebooted?

In particular, if I open the "messages" log (https://storage.cloud.google.com/chromeos-autotest-results/267325746-chromeos-test/chromeos2-row3-rack9-host11/crashinfo.chromeos2-row3-rack9-host11/var/log/messages), scroll to the end and then scroll up to the last lines before the reboot, I can see:

2018-12-15T04:29:27.580883-08:00 NOTICE pre-shutdown[6528]: Shutting down for reboot: system-update

Do we have a race condition somewhere that allows an update and test to run at the same time?