Use PhutilClassMapQuery instead of PhutilSymbolLoader

Summary: Use `PhutilClassMaQuery` instead of `PhutilSymbolLoader`, mostly for consistency. Depends on D13588.

Test Plan: Poked around a bunch of pages.

Reviewers: #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D13589

scripts/ssh/ssh-exec.php

@@ -190,11 +190,10 @@ try {
         $user->getUsername()));
   }
 
-  $workflows = id(new PhutilSymbolLoader())
+  $workflows = id(new PhutilClassMapQuery())
     ->setAncestorClass('PhabricatorSSHWorkflow')
-    ->loadObjects();
-
-  $workflow_names = mpull($workflows, 'getName', 'getName');
+    ->setUniqueMethod('getName')
+    ->execute();
 
   if (!$original_argv) {
     throw new Exception(
@@ -210,7 +209,7 @@ try {
         $user->getUsername(),
         'git clone',
         'hg push',
-        implode(', ', $workflow_names)));
+        implode(', ', array_keys($workflows))));
   }
 
   $log_argv = implode(' ', $original_argv);