init (Vue.prototype._init)
initMixin(Vue) // _init()
initState<br>初始化数据
initData
observe
class Observer
Array<br>原型覆盖
Obj
this.walk
defineReactive<br>数据响应式
class Dep<br>发布订阅模式
addSub
depend
notify
get
set
vm.$mount (拓写)
mountComponent
class Watcher
get
addDep
update
queueWatcher
nextTick($nextTick)
timerFunc
flushCallbacks
run
updateComponent<br>更新组件的fn
$mount(原生)
