payment-request-in-iframe-allowed.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>Test for PaymentRequest in an iframe</title>
<script src="../resources/testharness.js"></script>
<script src="../resources/testharnessreport.js"></script>
<iframe allowpaymentrequest srcdoc="
<!DOCTYPE html>
<meta charset='utf-8'>
<script>
window.top.test(function() {
        new PaymentRequest([{supportedMethods: ['foo']}], {total: {label: 'label', amount: {currency: 'USD', value: '5.00'}}});
    }, 'Scripts in the iframe element with allowpaymentrequest content attribute are allowed to make payment requests.');
</script>
"></iframe>

chromium/third_party/blink/web_tests/payments/payment-request-in-iframe-allowed.html