Add NegotiatedSerializer to config

pkg/client/unversioned/helper.go

@@ -231,6 +231,9 @@ func SetKubernetesDefaults(config *restclient.Config) error {
 	// TODO: Unconditionally set the config.Version, until we fix the config.
 	copyGroupVersion := g.GroupVersion
 	config.GroupVersion = &copyGroupVersion
+	if config.NegotiatedSerializer == nil {
+		config.NegotiatedSerializer = api.Codecs
+	}
 	if config.Codec == nil {
 		config.Codec = api.Codecs.LegacyCodec(*config.GroupVersion)
 	}