Update Auth for handleRequest

Summary: Updates Auth app for handleRequest

Test Plan: Tested what I could, Log in, Log out, Change Password, New account, Verify account... but extra eyes very helpful here.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: epriestley, Korvin

Maniphest Tasks: T8628

Differential Revision: https://secure.phabricator.com/D13748

src/applications/auth/controller/PhabricatorAuthFinishController.php

@@ -15,9 +15,8 @@ final class PhabricatorAuthFinishController
     return true;
   }
 
-  public function processRequest() {
-    $request = $this->getRequest();
-    $viewer = $request->getUser();
+  public function handleRequest(AphrontRequest $request) {
+    $viewer = $this->getViewer();
 
     // If the user already has a full session, just kick them out of here.
     $has_partial_session = $viewer->hasSession() &&