Merge pull request #55650 from smarterclayton/make_unstructured_conversion

Automatic merge from submit-queue. 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>.

Move unstructured conversion into pkg/runtime

Scheme conversion should support unstructured conversion natively to
allow going from unstructured to typed and back. It is not a higher
level responsibility to do that conversion because the scheme is the
only one who knows what types it supports.

@liggitt @kubernetes/sig-cli-api-reviews I am going to make Scheme support unstructured in ConvertToVersion and Convert, which means resource.Builder and the CLI can get simpler for all existing use cases where versioned and unstructured need to coexist.

Kubernetes-commit: a67abac7654cc3e05618d41191d71730cf9565ac

vendor/k8s.io/apimachinery/pkg/runtime/serializer/json/json.go

@@ -150,9 +150,10 @@ func (s *Serializer) Decode(originalData []byte, gvk *schema.GroupVersionKind, i
 	}
 
 	if into != nil {
+		_, isUnstructured := into.(runtime.Unstructured)
 		types, _, err := s.typer.ObjectKinds(into)
 		switch {
-		case runtime.IsNotRegisteredError(err):
+		case runtime.IsNotRegisteredError(err), isUnstructured:
 			if err := jsoniter.ConfigFastest.Unmarshal(data, into); err != nil {
 				return nil, actual, err
 			}