Sandbox: https://codesandbox.io/s/cranky-kapitsa-op3jh

Repro: type "a" and then after a second "b"

Expected: Eventually you'll see "ab" in all fields. Pending "..." indicator goes away.

Actual: You'll keep seeing "a" in low pri field. Pending "..." indicator is stuck.
act(() => {
        _setText('B');
      });
      expect(Scheduler).toHaveYielded([
        'B',
        'A',
        'B',
        'Suspend! [B]',
        'Loading',
      ]);
      expect(Scheduler).toFlushAndYield([]);
      expect(ReactNoop.getChildren()).toEqual([span('B'), span('A')]);
      Scheduler.unstable_advanceTime(250);
      await advanceTimers(250);
      expect(Scheduler).toFlushAndYield([]);
      expect(ReactNoop.getChildren()).toEqual([span('B'), span('A')]);
      Scheduler.unstable_advanceTime(500);
      await advanceTimers(500);
      expect(ReactNoop.getChildren()).toEqual([
        span('B'),
        hiddenSpan('A'),
        span('Loading'),
      ]);
      Scheduler.unstable_advanceTime(250);
      await advanceTimers(250);
      expect(Scheduler).toHaveYielded(['Promise resolved [B]']);
      act(() => {
        expect(Scheduler).toFlushAndYield(['B']);
      });
      expect(ReactNoop.getChildren()).toEqual([span('B'), span('B')]);