R1:b3b30dde6ac9

Add options for hidding inlines to the Differential header banner

Summary:
Fixes T8909. Ref T12733.

UI attempts to follow the mock, but is a bit rough since PHUIXButtonView without text in this menu gets weird spacing, we don't have circular buttons yet, and PHUIXActionView without an icon also gets odd spacing.

Test Plan: {F5003125}

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T12733, T8909

Differential Revision: https://secure.phabricator.com/D18128