code: function () {
              var self = this;
              if (this._dirty) {
                  self._dirty = false;
                  return this.storage.save(this.data);
              } else {
                  return (new $.Deferred()).resolve().promise();
              }
          }
docs: Saves the prefs for this `Scope`.
  
  @return {Promise} promise resolved once the data is saved.