Avoid warning for non-existing LDAP users

[MorrisJobke]

• use user_ldap
• try to login a user that doesn't exist on LDAP nor in the internal DB
• expected: no warning level message (at most a message of level debug or info)
• actual:

{
    "Code": 0,
    "Exception": "Exception",
    "File": "apps/user_ldap/lib/User_LDAP.php",
    "Line": 117,
    "Message": "No user available for the given login name on ldap://server:389",
    "Trace": "
        #0 apps/user_ldap/lib/User_LDAP.php(133): OCA\\User_LDAP\\User_LDAP->getLDAPUserByLoginName('admin')
        #1 lib/private/User/Manager.php(201): OCA\\User_LDAP\\User_LDAP->checkPassword(*** sensitive parameters replaced ***)
        #2 core/Controller/LoginController.php(214): OC\\User\\Manager->checkPassword(*** sensitive parameters replaced ***)
        #3 [internal function]: OC\\Core\\Controller\\LoginController->tryLogin(*** sensitive parameters replaced ***)
        #4 lib/private/AppFramework/Http/Dispatcher.php(160): call_user_func_array(Array, Array)
        #5 lib/private/AppFramework/Http/Dispatcher.php(90): OC\\AppFramework\\Http\\Dispatcher->executeController(Object(OC\\Core\\Controller\\LoginController), 'tryLogin')
        #6 lib/private/AppFramework/App.php(111): OC\\AppFramework\\Http\\Dispatcher->dispatch(Object(OC\\Core\\Controller\\LoginController), 'tryLogin')
        #7 lib/private/AppFramework/Routing/RouteActionHandler.php(47): OC\\AppFramework\\App::main('LoginController', 'tryLogin', Object(OC\\AppFramework\\DependencyInjection\\DIContainer), Array)
        #8 [internal function]: OC\\AppFramework\\Routing\\RouteActionHandler->__invoke(Array)
        #9 lib/private/Route/Router.php(293): call_user_func(Object(OC\\AppFramework\\Routing\\RouteActionHandler), Array)
        #10 lib/base.php(983): OC\\Route\\Router->match('/login')
        #11 index.php(48): OC::handleRequest()
        #12 {main}
    "
}

URL: /login?user=admin, app: user_ldap, log level: 3

cc @blizzz

[blizzz]

@MorrisJobke wasn't it the debug info that you have wanted once quite a while ago?

[MorrisJobke]

@MorrisJobke wasn't it the debug info that you have wanted once quite a while ago?

Correct, but not in the log level 3 (warning).

[blizzz]

so, removing it completely or downgrading to debug?

My bad, i somehow thought you wanted it removed. Sorry.

[MorrisJobke]

@blizzz Is this easy to accomplish?

[blizzz]

Here you go #2409