Repro case with a master build: https://codesandbox.io/s/stoic-mcnulty-dhygf?file=/src/App.js:668-703

Expected: we see content after a second.
Actual: fallback never resolves.

This happens in a sequence of:

1. Normal update
   - which suspends
2. Idle update
   - which also suspends
3. An unrelated normal update immediately followed by a ping (so they're batched)
   - here, we decide to stay on fallback, but should've shown the content

If you remove `_setVersion(v => v + 1);` on line 44 then the issue goes away.
expect(ReactNoop.getChildren()).toEqual([span('A')]);
      
      React.unstable_withSuspenseConfig(
        () => ReactNoop.render(<App page="B" />),
        SUSPENSE_CONFIG,
      );
      expect(Scheduler).toFlushAndYield(['Suspend! [B]', 'Loading...']);
      Scheduler.unstable_advanceTime(1000);
      await advanceTimers(1000);
      
      expect(ReactNoop.getChildren()).toEqual([span('A')]);
      Scheduler.unstable_advanceTime(1100);
      await advanceTimers(1100);
      
      expect(ReactNoop.getChildren()).toEqual([
        hiddenSpan('A'),
        span('Loading...'),
      ]);
      
      Scheduler.unstable_advanceTime(3000);
      await advanceTimers(3000);
      expect(Scheduler).toHaveYielded(['Promise resolved [B]']);
      expect(Scheduler).toFlushAndYield(['B']);
      expect(ReactNoop.getChildren()).toEqual([span('B')]);
    });
    
    it('hooks', async () => {
      let transitionToPage;
      function App() {
        const [page, setPage] = React.useState('none');