<html>
<head>
<meta charset="utf-8">
<base href="http://example.com/大洗あんこう祭り/">
</head>
<body>
<a id="a" href="foo.html"></a>
<div id="result"></div>
<script>
if (window.testRunner)
testRunner.dumpAsText();
document.getElementById('result').innerText = document.getElementById('a').href;
</script>
</body>
</html>