Automatic merge from submit-queue
Generates DELETE pod update operations
fixes#27105
Generates DELETE pod update operations to make the code and log more intuitive.
1. main refactoring is in `kubelet/config`
2. kubelet will log if it received DELETE, just like other OPs
cc @Random-Liu :)
Add `kube-reserved` and `system-reserved` flags for configuration
reserved resources for usage outside of kubernetes pods. Allocatable is
provided by the Kubelet according to the formula:
```
Allocatable = Capacity - KubeReserved - SystemReserved
```
Also provides a method for estimating a reasonable default for
`KubeReserved`, but the current implementation probably is low and needs
more tuning.
Change all references to the container ID in pkg/kubelet/... to the
strong type defined in pkg/kubelet/container: ContainerID
The motivation for this change is to make the format of the ID
unambiguous, specifically whether or not it includes the runtime
prefix (e.g. "docker://").
Add a new latency metric for the time from seeing the pod for the first time
to starting a pod worker for it.
Also, change PodStartLatency to include this initial processing latency.