Automatic merge from submit-queue (batch tested with PRs 53631, 56960). 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>.
Remove unused code in UT files in pkg/
**What this PR does / why we need it**:
Remove unused code in UT files in pkg/ .
**Release note**:
```release-note
NONE
```
Automatic merge from submit-queue
rkt: Add post-start hook support.
This adds a poll-and-timeout procedure after the pod is
started, to make sure the post-start hooks execute when the
container is actually running.
This is a temporal workaround for implementing post-hooks,
a long term solution is to use lifecycle event to trigger
those hooks, see https://github.com/kubernetes/kubernetes/issues/23084.
Also this fixes a bug of getting container ID for a non-running
container when running pre-stop hook.
cc @sjpotter @euank @kubernetes/sig-node
This adds a poll-and-timeout procedure after the pod is
started, to make sure the post-start hooks execute when the
container is actually running.
This is a temporal workaround for implementing post-hooks,
a long term solution is to use lifecycle event to trigger
those hooks, see https://github.com/kubernetes/kubernetes/issues/23084.
Also this fixes a bug of getting container ID for a non-running
container when running pre-stop hook.
This is implemented via touching a file on stop as a hook in the systemd
unit. The ctime of this file is then used to get the `finishedAt` time
in the future.
In addition, this changes the `startedAt` and `createdAt` to use the api
server's results rather than the annotations it previously used.
It's possible we might want to move this into the api in the future.
Fixes#23887
Add GeneratePodHostNameAndDomain() to RuntimeHelper to
get the hostname of the pod from kubelet.
Also update the logging flag to change the journal match from
_HOSTNAME to _MACHINE_ID.
