R1:1602858b2662

Possible fix for JX.History spookiness?

Summary: Ref T7573. I only got this reproducing like 10% of the time in Firefox but I can't reproduce it anymore after this change.

Test Plan:
- Added some logging.
- Saw Firefox handing us nonsense state values (?)
- Read the Firefox documentation?
- Maybe state is expected to be an object? This shouldn't matter?
- I don't really know?

iiam

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T7573

Differential Revision…