chromium/third_party/blink/web_tests/fast/frames/contentWindow_iFrame.html

<html>
<head>
<script>
    function putText() {
        if (window.testRunner) {
            testRunner.dumpAsText();
        }
        var w = document.getElementById("my_iframe").contentWindow;
        var d = document.getElementById("my_div");
        var result = w.location == "about:blank" ? "PASS" : "FAIL";
        d.innerText = result;
    }
</script>
</head>
<body onload="putText()">
<div>Testing contentWindow on Frames. Test passes if there is a 'PASS' line.
<iframe id="my_iframe" src="about:blank"></iframe>
</div>
<div id="my_div">div text will be replaced</div>
</body>
</html>