chromium/chrome/test/data/autofill/autofill_creditcard_form_in_oopif.html

<!DOCTYPE html>
<html>
  <head>
 <title>Credit Card Form in an Out-of-Process iframe</title>
 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
 </head>
 <body>
  <p>Credit Card Form in an Out-of-Process iframe</p>
  <iframe width="100%" height="800px"></iframe>
  <script>
    var url = window.location.href;
    url = url.replace(/a\.com/, "b.com");
    url = url.replace(/autofill_creditcard_form_in_oopif\.html/, "autofill_creditcard_form.html");
    document.querySelector('iframe').setAttribute('src', url);
  </script>
 </body>
</html>