Of course this should be a string now

Signed-off-by: Joas Schilling <coding@schilljs.com>

lib/Chat/ChatManager.php

@@ -151,7 +151,7 @@ class ChatManager {
 	 * @param Room $chat
 	 */
 	public function deleteMessages(Room $chat) {
-		$this->commentsManager->deleteCommentsAtObject('chat', $chat->getId());
+		$this->commentsManager->deleteCommentsAtObject('chat', (string) $chat->getId());
 
 		$this->notifier->removePendingNotificationsForRoom($chat);
 	}

lib/Notification/Notifier.php

@@ -81,7 +81,7 @@ class Notifier implements INotifier {
 		$l = $this->lFactory->get('spreed', $languageCode);
 
 		try {
-			$room = $this->manager->getRoomByToken((int) $notification->getObjectId());
+			$room = $this->manager->getRoomByToken($notification->getObjectId());
 		} catch (RoomNotFoundException $e) {
 			try {
 				// Before 3.2.3 the id was passed in notifications