Catch exception in differential

Summary:
This masks possible configuration issues and slightly degrades functionality
with the tradeoff of having differential work when phabricator isn't quite
configured correctly.

Test Plan:
remove directory for a repository, load differential revision from that repo,
and see differential load.

Reviewers: epriestley, vrana

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T2512

Differential Revision: https://secure.phabricator.com/D4859

src/applications/differential/view/DifferentialChangesetListView.php

@@ -251,10 +251,15 @@ final class DifferentialChangesetListView extends AphrontView {
 
     $repository = $this->repository;
     if ($repository) {
-      $meta['diffusionURI'] = (string)$repository->getDiffusionBrowseURIForPath(
+      try {
+        $meta['diffusionURI'] =
+          (string)$repository->getDiffusionBrowseURIForPath(
             $changeset->getAbsoluteRepositoryPath($repository, $this->diff),
             idx($changeset->getMetadata(), 'line:first'),
             $this->getBranch());
+      } catch (DiffusionSetupException $e) {
+        // Ignore
+      }
     }
 
     $change = $changeset->getChangeType();