Default newPage() to device-ready
Ref T9690. The "meta viewport" tag got dropped by accident because of the sort of weird logic on the old flow.
Make the default device-ready, then just turn it off for the tiny number of non-device pages.
- Verified meta viewport tag appears on normal pages again.
- Verified it doesn't show up on non-mobile pages like Maniphest Reports.
Reviewed By: chad
Maniphest Tasks: T9690
Differential Revision: https://secure.phabricator.com/D14396