Fix psalm issues related to the user backend

- Reflect the actual return value returned by the implementation in the
  the interface. E.g. IUser|bool -> IUser|false
- Remove $hasLoggedIn parameter from private countUser implementation.
  Replace the two call with the equivalent countSeenUser
- getBackend is nuallable, add this to the interface
- Use backend interface to make psalm happy about call to undefined
  methods. Also helps with getting rid at some point of the old
  implementActions

Signed-off-by: Carl Schwan <carl@carlschwan.eu>

1 files changed, 2 insertions, 2 deletions

diff --git a/tests/lib/User/ManagerTest.php b/tests/lib/User/ManagerTest.php
index c8c1430d583..2536eee8441 100644
--- a/tests/lib/User/ManagerTest.php
+++ b/tests/lib/User/ManagerTest.php
@@ -609,7 +609,7 @@ class ManagerTest extends TestCase {
 	public function testCountUsersOnlySeen() {
 		$manager = \OC::$server->getUserManager();
 		// count other users in the db before adding our own
-		$countBefore = $manager->countUsers(true);
+		$countBefore = $manager->countSeenUsers();
 
 		//Add test users
 		$user1 = $manager->createUser('testseencount1', 'testseencount1');
@@ -623,7 +623,7 @@ class ManagerTest extends TestCase {
 		$user4 = $manager->createUser('testseencount4', 'testseencount4');
 		$user4->updateLastLoginTimestamp();
 
-		$this->assertEquals($countBefore + 3, $manager->countUsers(true));
+		$this->assertEquals($countBefore + 3, $manager->countSeenUsers());
 
 		//cleanup
 		$user1->delete();