chromium/third_party/blink/web_tests/fast/harness/internals-object.html

<html>
<head>
<script>

if (window.testRunner)
    testRunner.dumpAsText();

function runTest()
{
    var log = document.body.appendChild(document.createElement('div'));
    log.write = function(msg, success)
    {
        this.appendChild(document.createElement('div')).textContent = msg + ': ' + (success ? 'PASS' : 'FAIL');
    }

    log.write('window.internals object should be visible when running in DRT', !!window.internals);
}

</script>
</head>
<body onload="runTest()">
</body>
</html>