message: perf(@vant/use): remove raf polyfill
diff: export const inBrowser = typeof window !== 'undefined';
  -const root = (inBrowser ? window : global) as Window;
  -
  -let prev = Date.now();
  -
  -function rafPolyfill(fn: FrameRequestCallback): number {
  - const curr = Date.now();
  - const ms = Math.max(0, 16 - (curr - prev));
  - const id = setTimeout(fn, ms);
  - prev = curr + ms;
  - return id;
  -}
  -
  export function raf(fn: FrameRequestCallback): number {
  - const requestAnimationFrame = root.requestAnimationFrame || rafPolyfill;
  - return requestAnimationFrame.call(root, fn);
  + return inBrowser ? requestAnimationFrame(fn) : -1;
  }
  export function cancelRaf(id: number) {
  - const cancelAnimationFrame = root.cancelAnimationFrame || root.clearTimeout;
  - cancelAnimationFrame.call(root, id);
  + if (inBrowser) {
  + cancelAnimationFrame(id);
  + }
  }
  // double raf for animation
  