message: refactor: also clone vnode.asyncFactory
diff: @@ -19,10 +19,10 @@ export default class VNode {
  isComment: boolean; // empty comment placeholder?
  isCloned: boolean; // is a cloned node?
  isOnce: boolean; // is a v-once node?
  - asyncFactory: ?Function; // async component factory function
  - asyncMeta: ?Object;
  + asyncFactory: Function | void; // async component factory function
  + asyncMeta: Object | void;
  isAsyncPlaceholder: boolean;
  - ssrContext: ?Object;
  + ssrContext: Object | void;
  constructor (
  tag?: string,
  @@ -87,7 +87,8 @@ export function cloneVNode (vnode: VNode): VNode {
  vnode.text,
  vnode.elm,
  vnode.context,
  - vnode.componentOptions
  + vnode.componentOptions,
  + vnode.asyncFactory
  )
  cloned.ns = vnode.ns
  cloned.isStatic = vnode.isStatic
  