Automatic merge from submit-queue (batch tested with PRs 64283, 67910, 67803, 68100). If you want to cherry-pick this change to another branch, please follow the instructions here: https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md. Adding GCE node termination handler as an optional addon. This step is a pre-requisite for auto-deploying that addon in GKE cc @mikedanese