Allow View Standalone in Diff preview

Test Plan: Click View Standalone.

Reviewers: epriestley, jungejason

Reviewed By: jungejason

CC: aran

Differential Revision: https://secure.phabricator.com/D2225

src/applications/differential/controller/diffview/DifferentialDiffViewController.php

@@ -116,6 +116,7 @@ final class DifferentialDiffViewController extends DifferentialController {
     $details = id(new DifferentialChangesetListView())
       ->setChangesets($changesets)
       ->setRenderingReferences($refs)
+      ->setStandaloneURI('/differential/changeset/')
       ->setUser($request->getUser());
 
     return $this->buildStandardPageResponse(