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

Notice the flash. I'd expect `suspended` to be `true` during the high pri render.
fiber: Fiber,
): null | HydratableInstance {
  if (!supportsHydration) {
    invariant(
      false,
      'Expected skipPastDehydratedSuspenseInstance() to never be called. ' +
        'This error is likely caused by a bug in React. Please file an issue.',
    );
  }
  let suspenseState: null | SuspenseState = fiber.memoizedState;
  let suspenseInstance: null | SuspenseInstance =
    suspenseState !== null ? suspenseState.dehydrated : null;
  invariant(
    suspenseInstance,
    'Expected to have a hydrated suspense instance. ' +
      'This error is likely caused by a bug in React. Please file an issue.',
  );
  return getNextHydratableInstanceAfterSuspenseInstance(suspenseInstance);
}
function popToNextHostParent(fiber: Fiber): void {