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.
currentHook = null;
  workInProgressHook = null;
  if (__DEV__) {
    hookTypesDev = null;
    hookTypesUpdateIndexDev = -1;
    currentHookNameInDev = null;
    isUpdatingOpaqueValueInRenderPhase = false;
  }
  didScheduleRenderPhaseUpdate = false;
}
function mountWorkInProgressHook(): Hook {
  const hook: Hook = {
    memoizedState: null,
    baseState: null,
    baseQueue: null,
    queue: null,
    next: null,
  };
  if (workInProgressHook === null) {
    
    currentlyRenderingFiber.memoizedState = workInProgressHook = hook;
  } else {
    
    workInProgressHook = workInProgressHook.next = hook;
  }
  return workInProgressHook;
}
function updateWorkInProgressHook(): Hook {