Automatic merge from submit-queue (batch tested with PRs 63151, 63795, 63553, 64068, 64113). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Implement watch-based secret manager
Initial experiments on 5000-node Kubemark show that apiserver is handling those with no real issues.
That said, we shouldn't enable it in prod without much more extensive scalability tests (so most probably not in 1.11), but having that in would enable easier testing.
@liggitt
0ea35f4c61