chromium/third_party/blink/web_tests/external/wpt/html/cross-origin-embedder-policy/resources/load-corp-images.html

<!doctype html>
<html>
<script src="/common/get-host-info.sub.js"></script>
<script>

function remote(path) {
  const REMOTE_ORIGIN = get_host_info().HTTPS_REMOTE_ORIGIN;
  return new URL(path, REMOTE_ORIGIN);
}

let params = new URLSearchParams(location.search);
let token = params.get('token');
let revalidate = params.get('revalidate');

let image_path = `/html/cross-origin-embedder-policy/resources/corp-image.py?token=${token}&revalidate=${revalidate}`;

window.addEventListener("load", async () => {
  await new Promise(resolve => {
    let img = document.createElement("img");
    img.src = remote(image_path);
    img.onload = () => { window.parent.postMessage({corp: false, loaded: true}, "*"); resolve(); };
    img.onerror = (e) => { window.parent.postMessage({corp: false, loaded: false}, "*"); resolve(); };
    document.body.appendChild(img);
  });

  await new Promise(resolve => {
    let img = document.createElement("img");
    img.src = remote(image_path + "&corp-cross-origin=1");
    img.onload = () => { window.parent.postMessage({corp: true, loaded: true}, "*"); resolve(); };
    img.onerror = (e) => { window.parent.postMessage({corp: true, loaded: false}, "*"); resolve(); };
    document.body.appendChild(img);
  });

  window.parent.postMessage({done: true}, "*")
});

</script>
</html>