chromium/chrome/test/data/extensions/api_test/extension_resource_request_policy/web_accessible/xhr_inaccessible_resource.html

<script>
  // Copyright 2012 The Chromium Authors
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  try {
    req = new XMLHttpRequest;
    req.open("GET",
             "chrome-extension://ggmldgjhdenlnjjjmehkomheglpmijnf/test2.png",
             false);
    req.send();
    document.title = 'XHR completed with status: ' + req.status;
  } catch (e) {
    document.title='XHR failed to load resource';
  }
</script>