Disable full screen mode for inline comments

Summary:
Full screen is a little foobar so disabling it for inline comments
Fixes T5272

Test Plan:
View inline comment after change, make sure full screen option
has gone.

Reviewers: epriestley, Blessed Reviewers

Reviewed By: epriestley, Blessed Reviewers

Subscribers: epriestley, Korvin

Maniphest Tasks: T5272

Differential Revision: https://secure.phabricator.com/D9579