chromium/third_party/blink/web_tests/fast/loader/frame-src-change-added-to-history.html

<html>
<head>
<script>

if (window.testRunner) {
  testRunner.dumpAsText();
  testRunner.dumpChildFrames();
  testRunner.dumpBackForwardList();
  testRunner.waitUntilDone();
}

var count = 4;

function frameLoaded() {
  if (count == 0) {
    if (window.testRunner)
      testRunner.notifyDone();
  } else {
    document.getElementsByTagName('iframe')[0].src = "data:," + count--;
  }
}

</script>
</head>
<body>
<iframe onload="setTimeout(frameLoaded, 0)"></iframe>
</body>
</html>