chromium/third_party/blink/web_tests/external/wpt/content-security-policy/navigate-to/support/navigate_parent.sub.html

<!DOCTYPE html>
<head>
  <script src="/resources/testharness.js"></script>
  <script src="/resources/testharnessreport.js"></script>

  <script>
    window.addEventListener('securitypolicyviolation', function(e) {
      top.postMessage({result: 'fail', violatedDirective: e.violatedDirective}, '*');
    });
  </script>
</head>

<body>
<a href="post_message_to_frame_owner.html" id="link" target="_parent">dummy link</a>
<script>
  document.getElementById('link').click();
</script>
</body>