Remove dust from page construction

Summary:
  ^\s+(['"])dust\1\s*=>\s*true,?\s*$\n

Test Plan: Looked through the diff.

Reviewers: chad

Reviewed By: chad

CC: aran

Differential Revision: https://secure.phabricator.com/D6769

src/applications/auth/controller/PhabricatorAuthStartController.php

@@ -139,7 +139,6 @@ final class PhabricatorAuthStartController
       array(
         'title' => pht('Login to Phabricator'),
         'device' => true,
-        'dust' => true,
       ));
   }