Add Owners search to Diffusion

Test Plan:
/diffusion/X/browse/:/file
Click Search Owners.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, epriestley

Differential Revision: https://secure.phabricator.com/D1572

src/applications/diffusion/controller/base/DiffusionController.php

@@ -97,6 +97,15 @@ abstract class DiffusionController extends PhabricatorController {
           ),
           $name));
     }
+    $nav->addNavItem(
+      phutil_render_tag(
+        'a',
+        array(
+          'href'  => '/owners/view/search/'.
+            '?repository='.phutil_escape_uri($callsign).
+            '&path='.phutil_escape_uri('/'.$drequest->getPath()),
+        ),
+        'Search Owners'));
 
     return $nav;
   }