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

<html>
  <head><title>This is a test page with a x-site frames</title>
  </head>
  <body>
    <iframe name="navFrame" src="https://REPLACE_WITH_HOST_AND_PORT/title1.html" id="navFrame"></iframe>
  </body>
</html>