Add "Open Revisions" builtin query for differential, and have links for both

code reviews and patches on welcome page.

src/applications/differential/query/DifferentialRevisionSearchEngine.php

@@ -199,6 +199,7 @@ final class DifferentialRevisionSearchEngine
       $names['authored'] = pht('Authored');
     }
 
+    $names['open'] = pht('Open Revisions');
     $names['all'] = pht('All Revisions');
 
     return $names;
@@ -218,6 +219,9 @@ final class DifferentialRevisionSearchEngine
       case 'authored':
         return $query
           ->setParameter('authorPHIDs', array($viewer->getPHID()));
+      case 'open':
+        return $query
+          ->setParameter('status', DifferentialRevisionQuery::STATUS_OPEN);
       case 'all':
         return $query;
     }

webroot/rsrc/custom/static/welcome.html

@@ -4,8 +4,8 @@
   <ul>
     <li><a href="maniphest/project/2/type/Bug/">Browse Bugs</a></li>
     <li><a class="button grey" href="maniphest/task/create/?project=2&type=Bug">Report Bug »</a></li>
-    <li><a href="maniphest/project/2/type/Patch/">Browse Patches</a></li>
-    <li><a class="button grey" href="differential/diff/create/">Submit Patch »</a></li>
+    <li><a href="differential/query/open/">Code Reviews</a> | <a href="maniphest/project/2/type/Patch/">Patches</a></li>
+    <li><a class="button grey" href="differential/diff/create/">Submit Code »</a></li>
   </ul>
 </div>