Automatic merge from submit-queue (batch tested with PRs 41667, 41820, 40910, 41645, 41361)
Allow multiple mounts in StatefulSet volume zone placement
We have some heuristics that ensure that volumes (and hence stateful set
pods) are spread out across zones. Sadly they forgot to account for
multiple mounts. This PR updates the heuristic to ignore the mount name
when we see something that looks like a statefulset volume, thus
ensuring that multiple mounts end up in the same AZ.
Fix#35695
```release-note
Fix zone placement heuristics so that multiple mounts in a StatefulSet pod are created in the same zone
```
We have some heuristics that ensure that volumes (and hence stateful set
pods) are spread out across zones. Sadly they forgot to account for
multiple mounts. This PR updates the heuristic to ignore the mount name
when we see something that looks like a statefulset volume, thus
ensuring that multiple mounts end up in the same AZ.
Fix#35695
1. pcb and pcb controller are removed and their functionality is
encapsulated in StatefulPodControlInterface.
2. IdentityMappers has been removed to clarify what properties of a Pod are
mutated by the controller. All mutations are performed in the
UpdateStatefulPod method of the StatefulPodControlInterface.
3. The statefulSetIterator and petQueue classes are removed. These classes
sorted Pods by CreationTimestamp. This is brittle and not resilient to
clock skew. The current control loop, which implements the same logic,
is in stateful_set_control.go. The Pods are now sorted and considered by
their ordinal indices, as is outlined in the documentation.
4. StatefulSetController now checks to see if the Pods matching a
StatefulSet's Selector also match the Name of the StatefulSet. This will
make the controller resilient to overlapping, and will be enhanced by
the addition of ControllerRefs.
