Phriction - stop leaking document titles you can't see

Summary: Fixes T6495. convert ad hoc query to a PhrictionDocumentQuery, thus enforcing view permissions

Test Plan: noted my test user a had a great wiki while test user b couldn't see most things.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Maniphest Tasks: T6495

Differential Revision: https://secure.phabricator.com/D10822