Automatic merge from submit-queue

Fix system container detection

```release-note
Fix system container detection in kubelet on systemd.

This fixed environments where CPU and Memory Accounting were not enabled on the unit 
that launched the kubelet or docker from reporting the root cgroup when 
monitoring usage stats for those components.
```

Fixes https://github.com/kubernetes/kubernetes/issues/25909

/cc @vishh @ncdc @eparis @wojtek-t - this reverts the revert https://github.com/kubernetes/kubernetes/issues/26478

This should merge when node e2e setups were updated per https://github.com/kubernetes/kubernetes/pull/26289