title: My first Chrome extension can't find default_popup page
body: <p>I'm following this tutorial to create a simple Hello World extension for Chrome:
  <a href="http://code.google.com/chrome/extensions/getstarted.html" rel="nofollow">http://code.google.com/chrome/extensions/getstarted.html</a>
  I have followed all the steps in that tutorial, and although I get to see the icon in the toolbar button, when I click the button I see a popup document with this error:</p>
  
  <blockquote>
    <p><strong>This webpage is not found</strong> No webpage was found for the web address:
    chrome-extension://mblkllehamdcncminlelggjfcbmkflbj/popup.html Error 6
    (net::ERR_FILE_NOT_FOUND): The file or directory could not be found.</p>
  </blockquote>
  
  <p>I have the popup.html and popup.js files in the same folder than the icon
  Here's my manifest.json contents:</p>
  
  <pre><code>{
    "name": "My First Extension",
    "version": "1.0",
    "manifest_version": 2,
    "description": "The first extension that I made.",
     "browser_action": {
      "default_icon": "icon.png",
      "default_popup": "popup.html"
    },
    "permissions": [
      "http://api.flickr.com/"
    ]
  }
  </code></pre>
  
  <p>Any idea what's wrong? (I've been googling for quite a while without success, looks like the point where I'm stuck at is no problem for anyone else...)</p>
  
  <p>Thanks in advance!</p>