dillon1000/react

Fix bugs related to unmounting error boundaries (#10403)

* Don't warn about setState on unmounted when scheduling error recovery

We shouldn't schedule an update on unmounted error boundaries, but we
don't know if a boundary is unmounted until we traverse its parents.
Added an additional argument to scheduleUpdate so we know not to warn
about setState on unmounted components.

* Should be able to unmount an error boundary before it is handled

Fixes the case where an error boundary captures an error, but its
parent is unmounted before we can re-render it. componentDidCatch is
never called, and we don't remove the boundary from our set of
unhandled error boundaries.

We should not assume that if capturedErrors is non-null that we still
have unhandled errors.