/**
  * Returns a list of event names that are used by active reaction rules.
  *
  * @return string[]
  *   The list of event names keyed by event name.
  */
 protected function getRegisteredEvents()
 {
     $events = [];
     foreach ($this->loadMultiple() as $rules_config) {
         foreach ($rules_config->getEventNames() as $event_name) {
             $event_name = $this->eventManager->getEventBaseName($event_name);
             if (!isset($events[$event_name])) {
                 $events[$event_name] = $event_name;
             }
         }
     }
     return $events;
 }