Fix a string in PhabricatorObjectHandleData

Summary: This got copy/pasted at some point long in the past, it should clearly read "Task".

Test Plan: Looked at the rest of the strings.

Reviewers: btrahan, vrana

Reviewed By: vrana

CC: aran

Differential Revision: https://secure.phabricator.com/D3774

src/applications/phid/handle/PhabricatorObjectHandleData.php

@@ -313,7 +313,7 @@ final class PhabricatorObjectHandleData {
             $handle->setPHID($phid);
             $handle->setType($type);
             if (empty($tasks[$phid])) {
-              $handle->setName('Unknown Revision');
+              $handle->setName('Unknown Task');
             } else {
               $task = $tasks[$phid];
               $handle->setName($task->getTitle());