Migrate Project lock to modular transactions

Summary: See T12673

Test Plan: Unit tests pass. Locked and unlocked a project and saw timeline changes.

Reviewers: #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: epriestley

Differential Revision: https://secure.phabricator.com/D17986

src/applications/project/controller/PhabricatorProjectLockController.php

@@ -49,7 +49,8 @@ final class PhabricatorProjectLockController
       }
 
       $xactions[] = id(new PhabricatorProjectTransaction())
-        ->setTransactionType(PhabricatorProjectTransaction::TYPE_LOCKED)
+        ->setTransactionType(
+            PhabricatorProjectLockTransaction::TRANSACTIONTYPE)
         ->setNewValue($new_value);
 
       $editor = id(new PhabricatorProjectTransactionEditor())