In addition to a regular failure bug due to a merged or CQ'ed CL, there are few other common bug types filed by ChromeOS sheriffs. Please see  go/cros-sheriff-playbook .

1) A bug for infra deputies, e.g. not enough DUTs in a pool. This should have following properties:
 - Component: Infra>Client>ChromeOS
 - Status: Assigned
 - Owner: Primary infra deputy
 - CC: Primary and secondary infra deputies

2) A bug for lab device repair, see go/cros-lab-device-repair

3) A bug for build deputy. Personally I haven't had to use it, but it's mentioned as a common pattern in sheriff playbook.