Summary:
It's not immediately obvious from the UI/UX when/if this mechanism breaks, so it's good to have a test.
Changelog: [Internal] Fabric-specific internal change.
Reviewed By: JoshuaGross
Differential Revision: D21184718
fbshipit-source-id: 25432a1398cff3ce61f62cf433e3cb73d7a7a93f