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.
|};
export type FunctionComponentUpdateQueue = {|lastEffect: Effect | null|};
export type TimeoutConfig = {|
  timeoutMs: number,
|};
type BasicStateAction<S> = (S => S) | S;
type Dispatch<A> = A => void;
let renderExpirationTime: ExpirationTime = NoWork;
let currentlyRenderingFiber: Fiber = (null: any);
let currentHook: Hook | null = null;
let workInProgressHook: Hook | null = null;
let didScheduleRenderPhaseUpdate: boolean = false;
const RE_RENDER_LIMIT = 25;
let currentHookNameInDev: ?HookType = null;
let hookTypesDev: Array<HookType> | null = null;
let hookTypesUpdateIndexDev: number = -1;
let ignorePreviousDependencies: boolean = false;
function mountHookTypesDev() {
  if (__DEV__) {
    const hookName = ((currentHookNameInDev: any): HookType);
    if (hookTypesDev === null) {
      hookTypesDev = [hookName];
    } else {
      hookTypesDev.push(hookName);
    }
  }
}
function updateHookTypesDev() {
  if (__DEV__) {
    const hookName = ((currentHookNameInDev: any): HookType);