Chromedriver still runs after app.close() on Windows

• spectron 3.2.6
• Windows 7 amd64

// test.js
var electronPath = require('electron-prebuilt')
var Application  = require('spectron').Application
var delay = require('timeout-as-promise')

let app = new Application({
    path: electronPath,
    args: ['.'],
});

app.start()
    .then(() => {
        console.log('wait 3 sec')
        return delay(3000)
    })
    .then(() => {
        console.log('ask to stop')
        return app.stop()
    })
    .then(() => {
        console.log('stopped')
    })

Output is

wait 3 sec
ask to stop
stopped

The electron app is correctly closed but the chromedriver.exe still runs, and the nodejs script test.js never quits.

This bug does not occurs under Linux (archlinux)

Start by running the issue's test.js reproduction on Windows 7 with spectron 3.2.6, then inspect the app.start() and app.stop() lifecycle involved in the example. Done means the Electron app closes, chromedriver.exe exits, and the Node.js process terminates as it does on Linux.