chore: Refactor callForSeenUsers to use getSeenUsers

Signed-off-by: Louis Chemineau <louis@chmn.me>

lib/private/User/Manager.php

@@ -628,30 +628,14 @@ class Manager extends PublicEmitter implements IUserManager {
 		return $result;
 	}
 
-	/**
-	 * @param \Closure $callback
-	 * @psalm-param \Closure(\OCP\IUser):?bool $callback
-	 * @since 11.0.0
-	 */
 	public function callForSeenUsers(\Closure $callback) {
-		$limit = 1000;
-		$offset = 0;
-		do {
-			$userIds = $this->getSeenUserIds($limit, $offset);
-			$offset += $limit;
-			foreach ($userIds as $userId) {
-				foreach ($this->backends as $backend) {
-					if ($backend->userExists($userId)) {
-						$user = $this->getUserObject($userId, $backend, false);
-						$return = $callback($user);
-						if ($return === false) {
-							return;
-						}
-						break;
-					}
-				}
+		$users = $this->getSeenUsers();
+		foreach ($users as $user) {
+			$return = $callback($user);
+			if ($return === false) {
+				return;
 			}
-		} while (count($userIds) >= $limit);
+		}
 	}
 
 	/**