Automatic merge from submit-queue (batch tested with PRs 47850, 47835, 46197, 47250, 48284)
Populate endpoints for headless service with no ports
**What this PR does / why we need it**:
- populate endpoints with headless service (thanks @fraenkel for the original PR!)
- allow ports with headless service
- nits
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes#32796https://github.com/kubernetes/kubernetes/issues/32796#issuecomment-270462724
**Special notes for your reviewer**:
/cc @thockin @fraenkel
**Release note**:
```release-note
NONE
```