This applies forked changes from the "new" reconciler to the "old" one.
Includes:
- d410f0a [FORKED] Bugfix: Offscreen instance is null during setState
- 58bb117 [FORKED] Check for infinite update loops even if unmounted
- 31882b5 [FORKED] Bugfix: Revealing a hidden update
- 17691ac [FORKED] Don't update childLanes until after current render