Send mail to targets in the user's translation

Summary: Ref T6367.

Test Plan:
  - Added and executed unit tests.
  - Sent mail to A (en_US) and B (en_A*).
  - Got one mail in English and one mail in ENGLISH.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T6367

Differential Revision: https://secure.phabricator.com/D13142

src/applications/base/controller/PhabricatorController.php

@@ -114,10 +114,7 @@ abstract class PhabricatorController extends AphrontController {
       $request->setUser($user);
     }
 
-    $locale_code = $user->getTranslation();
-    if ($locale_code) {
-      PhabricatorEnv::setLocaleCode($locale_code);
-    }
+    PhabricatorEnv::setLocaleCode($user->getTranslation());
 
     $preferences = $user->loadPreferences();
     if (PhabricatorEnv::getEnvConfig('darkconsole.enabled')) {