Check is viewer is a participant before showing count

Summary: In Conpherence ProfileMenuItem we show an unread count if you're a participant, but all message count if you're not. Just remove that.

Test Plan: Log out of room in Conpherence, leave messages on second account, check menu item on both accounts.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin

Differential Revision: https://secure.phabricator.com/D17664

src/applications/search/menuitem/PhabricatorConpherenceProfileMenuItem.php

@@ -102,8 +102,13 @@ final class PhabricatorConpherenceProfileMenuItem
       return array();
     }
 
+    $participants = $room->getParticipants();
+    $viewer_phid = $viewer->getPHID();
+    $unread_count = null;
+    if (isset($participants[$viewer_phid])) {
       $data = $room->getDisplayData($viewer);
       $unread_count = $data['unread_count'];
+    }
 
     $count = null;
     if ($unread_count) {