Codebase Browser
chromium
Go to App

chromium/third_party/blink/web_tests/external/wpt/xhr/header-user-agent-sync.htm 

<!DOCTYPE html>
<html>
<head>
    <title>Test that sync requests (both OPTIONS preflight and regular) are sent with the User-Agent header</title>
    <script src="/resources/testharness.js"></script>
    <script src="/resources/testharnessreport.js"></script>
    <script src="/common/get-host-info.sub.js"></script>
</head>
<body>
<script type="text/javascript">
  test(function() {
    let xhr = new XMLHttpRequest;
    xhr.open("post", get_host_info().HTTP_REMOTE_ORIGIN + "/xhr/resources/header-user-agent.py", false);
    xhr.setRequestHeader("x-test", "foobar");
    xhr.send();
    assert_equals(xhr.responseText, "PASS");
  }, "Sync request has User-Agent header");
</script>
</body>
</html>