dillon1000/react

Properly clean up gesture Animations (#35559)

Follow up to #35337.

During a gesture, we always cancel the original animation and create a
new one that we control. That's the one we need to add to the set that
needs to be cancelled. Otherwise future gestures hang.

An unfortunate consequence is that any custom ones that you start e.g.
with #35556 or through other means aren't automatically cleaned up (in
fact there's not even a clean up callback yet). This can lead these to
freeze the whole UI afterwards. It would be really good to get this
fixed in browsers instead so we can revert #35337.