title: chrome:// Invalid Scheme
body: <p>I've enabled "chrome://flags/#extensions-on-chrome-urls" which should allow me to create extensions that can run on chrome:// sites. When I try to unpack my extension, however, it fails with the error message: "Invalid value for 'content_scripts[0].matches[0]': Invalid scheme." I don't believe my script.js is a problem since the unpacking doesn't fail when I replace the "chrome://extensions" part with an http or https sites. Any help would be greatly appreciated, does anyone know a fix?</p>
  
  <p>manifest.json:</p>
  
  <pre><code>{
    "name": "Does something on chrome://extensions",
    "version": "1.2",
    "description": "Read the name",
    "manifest_version": 2,
      "browser_action": {
      "default_title": "Ext",
      "default_popup": "popup.html"
    },
    "content_scripts": [ {
      "matches": ["chrome://extensions"],
      "js": ["script.js"]
    } ]
  }
  </code></pre>