It seems that there might be some deadlock in MessageLoop.CanCreateConcurrentMessageLoop which runs 45 minutes in https://cirrus-ci.com/task/6032548447125504 until cancelled.

This at least means a flaky test. In the worst case, this might signal that our MessageLoop can sometimes hang on a user device. That's probably worse than a crash. Hence I'm giving it a severe: crash label even without crashing because I can't find a severe: hang label.

CC @chinmaygarde