dillon1000/react

Warn if addTransitionType is called when there are no pending Actions (#32793)

Stacked on #32792.

It's tricky to associate a specific `addTransitionType` call to a
specific `startTransition` call because we don't have `AsyncContext` in
browsers yet. However, we can keep track if there are any async
transitions running at all, and if not, warn. This should cover most
cases.

This also errors when inside a React render which might be a legit way
to associate a Transition Type to a specific render (e.g. based on props
changing) but we want to be a more conservative about allowing that yet.
If we wanted to support calling it in render, we might want to set which
Transition object is currently rendering but it's still tricky if the
render has `async function` components. So it might at least be
restricted to sync components (like Hooks).