Fix Differential flag view bug

Summary: See D3125#3

Test Plan:
Well, apparently the FB test Phabricator has no other flags
in it, so I modified the database by hand... the changed revision was
not marked as flagged in Differential.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T1557

Differential Revision: https://secure.phabricator.com/D3130

src/applications/differential/view/DifferentialRevisionListView.php

@@ -68,6 +68,7 @@ final class DifferentialRevisionListView extends AphrontView {
     }
 
     $flags = id(new PhabricatorFlagQuery())
+      ->withOwnerPHIDs(array($user->getPHID()))
       ->withObjectPHIDs(mpull($this->revisions, 'getPHID'))
       ->execute();
     $flagged = mpull($flags, null, 'getObjectPHID');