_onObjectActivated(props) {
    /**
     * The event when object is selected(aka activated).
     * @event ImageEditor#objectActivated
     * @param {ObjectProps} objectProps - object properties
     * @example
     * imageEditor.on('objectActivated', function(props) {
     *     console.log(props);
     *     console.log(props.type);
     *     console.log(props.id);
     * });
     */
    this.fire(events.OBJECT_ACTIVATED, props);
  }
'objectActivated' event handler
@param {ObjectProps} props - object properties
@private