chromium/third_party/blink/web_tests/fast/forms/text/textfield-outline.html

<html>
    <head>
        <script>
        function test()
        {
            var tf = document.getElementById('tf');
            tf.focus();
            if (window.testRunner) {
                eventSender.keyDown("a");
                eventSender.keyDown("b");
                eventSender.keyDown("c");
            }
        }
        </script>
    </head>
    <body onload="test()">
        This tests that a negative outline-offset won't get in the way of a cursor in a text control.<br>
        <input id="tf" style="font-size: 20px; border: solid thin black;" value="This tests that typing doesn't cut holes in the focus outline"></input>
    </body>
</html>