title: Dependency errors when using Puppeteer (Headless Chrome) with Vue + Webpack
body: <p>I'm using these two libraries/templates: </p>
  
  <p><a href="https://github.com/GoogleChrome/puppeteer" rel="nofollow noreferrer">https://github.com/GoogleChrome/puppeteer</a> (Headless Chrome)</p>
  
  <p><a href="https://github.com/vuejs-templates/pwa" rel="nofollow noreferrer">https://github.com/vuejs-templates/pwa</a> (Vue template using Webpack and Express).</p>
  
  <p>This is the code:</p>
  
  <pre><code>export default {
    mounted () {
      const puppeteer = require('puppeteer')
  
      ;(async () =&gt; {
        const browser = await puppeteer.launch()
        const page = await browser.newPage()
        await page.goto('https://www.google.com/search?tbm=bks&amp;q=%22this+is%22')
        const result = await page.evaluate(() =&gt; {
          const stats = document.querySelector('#resultStats')
          return stats.textContent
        })
        console.log(result)
        await browser.close()
      })()
    }
  }
  </code></pre>
  
  <p>I did <code>npm install</code> many times but I still have dependency errors:</p>
  
  <blockquote>
    <p>These dependencies were not found:</p>
    
    <ul>
    <li>child_process in ./node_modules/puppeteer/lib/Launcher.js, ./node_modules/puppeteer/node6/Launcher.js</li>
    <li>fs in ./node_modules/extract-zip/index.js, ./node_modules/extract-zip/node_modules/mkdirp/index.js and 18 others</li>
    </ul>
    
    <p>To install them, you can run: npm install --save child_process fs
    Listening at <a href="http://localhost:8080" rel="nofollow noreferrer">http://localhost:8080</a></p>
  </blockquote>
  
  <p>Node: I also did <code>npm install --save child_process fs</code> many times. Same error.</p>