code: func (r *crdHandler) GetCustomResourceListerCollectionDeleter(crd *apiextensions.CustomResourceDefinition) (finalizer.ListerCollectionDeleter, error) {
  	info, err := r.getOrCreateServingInfoFor(crd)
  	if err != nil {
  		return nil, err
  	}
  	return info.storages[info.storageVersion].CustomResource, nil
  }
docs: // GetCustomResourceListerCollectionDeleter returns the ListerCollectionDeleter of
  // the given crd.