Latest example:
Infra Failure: Step('read_logs') (canceled) (retcode: None) Infra Failure: Step('Killing Processes.kill chrome') (canceled) (retcode: None) Infra Failure: Step('OS info (2)') (canceled) (retcode: None) Task bot died. backend task is interrupted
From talking to Chromium folks:
Something is sending SIGTERM signal to the running build.
SSH to the machine and examine syslog, maybe there'll be a clue of what is sending this SIGTERM