Automatic merge from submit-queue (batch tested with PRs 36721, 46483, 45500, 46724, 46036)
Federation: Minor corrections in service controller and add a unit testcase
**What this PR does / why we need it**:
This PR fixes few outdated comments in federation service controller and few other minor fixes.
This also adds a unit test case to test federated service deletion.
/assign @quinton-hoole
/cc @marun @kubernetes/sig-federation-pr-reviews
```release-note
NONE
```
Automatic merge from submit-queue (batch tested with PRs 46429, 46308, 46395, 45867, 45492)
deduplicate endpoints before DNS registration
**What this PR does / why we need it**: Multizone clusters will return duplicated endpoints to the federation controller manager. The FCM will then attempt to create an A record with duplicate entries, which will fail. As a result, federated services on multi-AZ clusters don't work right now. This PR deduplicates the endpoint IPs before attempting the DNS record registration.
**Which issue this PR fixes**: fixes#35997
**Special notes for your reviewer**:
I believe there is a lot of refactoring required with multizone federated clusters, most notably with regard to AWS and optimising for ALIAS records rather than A, but this PR will at least allow basic functionality to work.
```release-note NONE
```
Automatic merge from submit-queue (batch tested with PRs 38212, 38792, 39641, 36390, 39005)
Updating federated service controller to support cascading deletion
Ref https://github.com/kubernetes/kubernetes/issues/33612
Service controller is special than other federation controllers because it does not use federatedinformer and updater to sync services (it was written before we had those frameworks).
Updating service controller code to instantiate these frameworks and then use deletion helper to perform cascading deletion.
Note that, I havent changed the queuing logic in this PR so we still dont use federated informer to manage the queue. Will do that in the next PR.
cc @kubernetes/sig-federation-misc @mwielgus @quinton-hoole
```release-note
federation: Adding support for DeleteOptions.OrphanDependents for federated services. Setting it to false while deleting a federated service also deletes the corresponding services from all registered clusters.
```
We can put subdomains into hosted zones (for example,
foo.federation.example.com can be hosted in example.com)
By allowing sharing a common hosted zone, this means the user doesn't
have to do as much setup.
