简记webpack运行报错 Uncaught TypeError: self.postMessage is not a function

说好2017Fix的还是能重现，可能项目的版本比较旧了，简要记录解决办法

1.错误：

index.js?bed3:67 Uncaught TypeError: self.postMessage is not a function
    at sendMsg (index.js?bed3:67)
    at Object.invalid (index.js?bed3:83)
    at SockJS.onmessage (socket.js?57b2:41)
    at SockJS.EventTarget.dispatchEvent (sockjs.js?3600:170)
    at eval (sockjs.js?3600:887)
    at Array.forEach (<anonymous>)
    at SockJS._transportMessage (sockjs.js?3600:885)
    at WebSocketTransport.EventEmitter.emit (sockjs.js?3600:86)
    at WebSocketTransport.ws.onmessage (sockjs.js?3600:2961)

2.  解决办法：打开文件 node_modules\webpack-dev-server\client\index.js ， 找到 67行（或sendMsg方法）补充类型判断条件   && typeof self === 'function'

　如图：