Automatic merge from submit-queue

Let kubelet log the DeletionTimestamp if it's not nil in update

This helps to debug if it's the kubelet to blame when a pod is not deleted. 

Example output:
```
SyncLoop (UPDATE, "api"): "redis-master_default(c6782276-2dd4-11e6-b874-64510650ab1c):DeletionTimestamp=2016-06-08T23:58:12Z"
```

ref #26290
cc @Random-Liu