Make logged-out users use global settings, not default settings

Summary: Fixes T11917. Give logged-out / omnipotent users the global settings, not the default settings.

Test Plan: Changed applications and language, logged out, saw changes as a public user.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T11917

Differential Revision: https://secure.phabricator.com/D16936