do not unref timer for let bug appear

src/puppet-web/event.js

@@ -107,6 +107,11 @@ function onBrowserDead(e) {
   .then(() => { // Finally
     log.verbose('PuppetWebEvent', 'onBrowserDead() new browser borned')
     this.isBrowserBirthing = false
+
+    this.emit('watchdog', {
+      data: `onBrowserDead() new browser borned`
+      , type: 'POISON'
+    })
   })
 }
 

src/puppet-web/watchdog.js

@@ -83,7 +83,7 @@ function setWatchDogTimer(timeout, feed) {
   log.silly('PuppetWebWatchdog', 'setWatchDogTimer(%d, %s)', timeout, feed)
 
   this.watchDogTimer = setTimeout(watchDogReset.bind(this, timeout, feed), timeout)
-  this.watchDogTimer.unref()
+  // this.watchDogTimer.unref()
   this.watchDogTimerTime = Date.now() + timeout
   // block quit, force to use quit() // this.watchDogTimer.unref() // dont block quit
 }
@@ -142,4 +142,4 @@ function monitorScan(type) {
   }
 }
 
-module.exports = Watchdog
\ No newline at end of file
+module.exports = Watchdog