fix(instance): clone options passed to save, closes #4681

lib/instance.js

@@ -494,7 +494,9 @@ Instance.prototype.save = function(options) {
   if (arguments.length > 1) {
   if (arguments.length > 1) {
     throw new Error('The second argument was removed in favor of the options object.');
     throw new Error('The second argument was removed in favor of the options object.');
   }
   }
-  options = _.defaults({}, options, {
+
+  options = this.$Model.$optClone(options || {});
+  options = _.defaults(options, {
     hooks: true,
     hooks: true,
     validate: true
     validate: true
   });
   });