chromium/third_party/blink/perf_tests/parser/html-parser.html

<!DOCTYPE html>
<body>
<script src="../resources/runner.js"></script>
<script>
var spec = PerfTestRunner.loadFile("resources/html5.html");

PerfTestRunner.measureTime({
    description: "Measures performance of the HTML parser.",
    run: function() {
        var iframe = document.createElement("iframe");
        iframe.style.display = "none";  // Prevent creation of the rendering tree, so we only test HTML parsing.
        iframe.sandbox = 'allow-same-origin';  // Prevent external script loads which could cause write() to return before completing the parse.
        document.body.appendChild(iframe);
        iframe.contentDocument.open();
        iframe.contentDocument.write(spec);
        iframe.contentDocument.close();
        document.body.removeChild(iframe);
    }
});

</script>
</body>