code: func NewRawStorage(config *storagebackend.Config) (storage.Interface, factory.DestroyFunc) {
  	s, d, err := factory.Create(*config)
  	if err != nil {
  		klog.Fatalf("Unable to create storage backend: config (%v), err (%v)", config, err)
  	}
  	return s, d
  }
docs: // NewRawStorage creates the low level kv storage. This is a work-around for current
  // two layer of same storage interface.
  // TODO: Once cacher is enabled on all registries (event registry is special), we will remove this method.