Index: wp-includes/js/media-models.js
===================================================================
--- wp-includes/js/media-models.js	(revision 22831)
+++ wp-includes/js/media-models.js	(working copy)
@@ -269,7 +269,7 @@
 
 			return media.post( 'save-attachment-compat', _.defaults({
 				id:     this.id,
-				nonce:  l10n.saveAttachmentNonce
+				nonce:  media.model.settings.saveAttachmentNonce
 			}, data ) ).done( function( resp, status, xhr ) {
 				model.set( model.parse( resp, xhr ), options );
 			});