dillon1000/react

Consolidate workLoop and deferredWork loop

Solves a few things:

- Moves code out of performWork into workLoop so that it can
be optimized.
- errorLoop (now clearErrors) is no longer called recursively.
- Removes a while (true) loop inside performWork (not that it really
matters for optimization, since performWork contains a try block and
will be deopted, anyway).