Replace old login validation controller with new one

Summary: Ref T1536. We can safely replace the old login validation controller with this new one, and reduce code dplication while we're at it.

Test Plan: Logged in with LDAP, logged in with OAuth, logged in with username/password, did a password reset.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T1536

Differential Revision: https://secure.phabricator.com/D6178

src/applications/auth/controller/PhabricatorLDAPLoginController.php

@@ -81,27 +81,18 @@ final class PhabricatorLDAPLoginController extends PhabricatorAuthController {
             ->setURI('/settings/panel/ldap/');
         }
 
-        if ($ldap_info->getID()) {
+        if ($ldap_info->getUserPHID()) {
           $unguarded = AphrontWriteGuard::beginScopedUnguardedWrites();
 
           $known_user = id(new PhabricatorUser())->loadOneWhere(
             'phid = %s',
             $ldap_info->getUserPHID());
 
-          $session_key = $known_user->establishSession('web');
-
           $this->saveLDAPInfo($ldap_info);
 
-          $request->setCookie('phusr', $known_user->getUsername());
-          $request->setCookie('phsid', $session_key);
+          $this->establishWebSession($known_user);
 
-          $uri = new PhutilURI('/login/validate/');
-          $uri->setQueryParams(
-            array(
-              'phusr' => $known_user->getUsername(),
-            ));
-
-          return id(new AphrontRedirectResponse())->setURI((string)$uri);
+          return $this->buildLoginValidateResponse($known_user);
         }
 
         $controller = newv('PhabricatorLDAPRegistrationController',