LayoutTests/http/tests/download/basic-ascii.html

<meta charset="koi8-r">
<script>
if (window.testRunner) {
    testRunner.dumpAsText();
    testRunner.setCustomPolicyDelegate(true, true);
}
</script>
<p>Download file name should be "test file.txt".</p>
<iframe src="resources/basic-ascii.php"></iframe>