chromium/third_party/blink/web_tests/external/wpt/html/browsers/origin/cross-origin-objects/resources/cross-origin-due-to-document-domain-only-helper.html

<!doctype html>
<meta charset=utf-8>
<script>
self.expandosForever = true
self.location.expandosForever = true
function setDocumentDomain() {
  document.domain = document.domain
}
</script>