code: function (eventDescriptor) {
          var me = this;
  
          // only fire keyframe event (and setup the eventDescriptor) once...
          if (!eventDescriptor.defer) {
              me.makeToken(eventDescriptor, 'done');
              me.fireEvent('keyframe', me, eventDescriptor);
          }
  
          return eventDescriptor.done;
      }
docs: This method is called when a keyframe is reached. This will fire the keyframe event.
  If the keyframe has been handled, true is returned. Otherwise, false is returned.
  @param {Object} eventDescriptor The event descriptor of the keyframe.
  @return {Boolean} True if the keyframe was handled, false if not.