Add search app icon

Summary: It's an icon. For Search. Fixes T3966

Test Plan: Search

Reviewers: epriestley, btrahan

Reviewed By: epriestley

CC: Korvin, epriestley, aran

Maniphest Tasks: T3966

Differential Revision: https://secure.phabricator.com/D7389

src/applications/search/application/PhabricatorApplicationSearch.php

@@ -18,6 +18,10 @@ final class PhabricatorApplicationSearch extends PhabricatorApplication {
     return pht('Find stuff in big piles.');
   }
 
+  public function getIconName() {
+    return 'search';
+  }
+
   public function shouldAppearInLaunchView() {
     return false;
   }