controller: drop extra rs deep-copy

pkg/controller/replicaset/replica_set_utils.go

@@ -26,7 +26,6 @@ import (
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/labels"
-	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/api/v1"
 	extensions "k8s.io/kubernetes/pkg/apis/extensions/v1beta1"
 	unversionedextensions "k8s.io/kubernetes/pkg/client/clientset_generated/clientset/typed/extensions/v1beta1"
@@ -46,14 +45,6 @@ func updateReplicaSetStatus(c unversionedextensions.ReplicaSetInterface, rs *ext
 		return rs, nil
 	}
 
-	// deep copy to avoid mutation now.
-	// TODO this method need some work.  Retry on conflict probably, though I suspect this is stomping status to something it probably shouldn't
-	copyObj, err := api.Scheme.DeepCopy(rs)
-	if err != nil {
-		return nil, err
-	}
-	rs = copyObj.(*extensions.ReplicaSet)
-
 	// Save the generation number we acted on, otherwise we might wrongfully indicate
 	// that we've seen a spec update when we retry.
 	// TODO: This can clobber an update if we allow multiple agents to write to the