Automatic merge from submit-queue (batch tested with PRs 63597, 63599). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
push ToRESTMapper down a layer
The RESTMapper is needed to drive some use-cases for a dynamic client and takes a little bit of wiring (nested restmappers). This pull pushes that into information derived from the kubeconfig flags to allow easy re-use.
@kubernetes/sig-cli-maintainers
/assign @juanvallejo
/assign @soltysh
assigned to original creators.
```release-note
NONE
```