chromium/chrome/test/data/ssl/page_with_unsafe_image.html

<html>
<head><title>Page with unsafe image</title>
<script>
  function ImageWidth() {
    return document.getElementById("bad_image").width;
  }
</script>
</head>

<body>
This page contains an image which is served over an insecure HTTPS connection...<br>
<img id="bad_image" src="https://REPLACE_WITH_HOST_AND_PORT/ssl/google_files/logo.gif"/>
</body>
</html>