Repro: https://codesandbox.io/s/fast-water-4i4jb

Notice the flash. I'd expect `suspended` to be `true` during the high pri render.
ReactNoop.render(
      <Fragment>
        <Suspense fallback={<Text text="Loading..." />} />
      </Fragment>,
    );
    expect(Scheduler).toFlushAndYield([]);
    ReactNoop.render(
      <Fragment>
        <Suspense fallback={<Text text="Loading..." />}>
          <AsyncText text="Async" ms={3000} />
        </Suspense>
        <Text text="Sync" />
      </Fragment>,
    );
    expect(Scheduler).toFlushAndYield([
      
      'Suspend! [Async]',
      'Loading...',
      
      'Sync',
    ]);
    
    expect(ReactNoop.getChildren()).toEqual([]);
    
    
    
    ReactNoop.expire(2000);
    await advanceTimers(2000);
    expect(Scheduler).toFlushWithoutYielding();
    expect(ReactNoop.getChildren()).toEqual([span('Loading...'), span('Sync')]);