* Prevent operation queue from running when synchronous source completes

Differentiate between synchronous operation queue runs and
scheduled/deferred queue runs by:
- Using nextOperation directly for non-queue runs
- Interrupting the queue when the source terminates
- Always scheduling a deferred queue flush even if it'll have nothing to flush

* Prevent dispatchOperation queue to run inside a queue

* Remove currentInit check to allow React to recursively continue work

* Add changeset