third_party/blink/web_tests/http/tests/origin_trials/feature-policy-reporting/feature-policy-reporting-js.php

<?php
# This test validates that feature policy report-only mode works when enabled
# by origin trial, with the trial token added by script.

header("Feature-Policy-Report-Only: sync-xhr 'none'");
?>
<title>Feature Policy Report-Only - test trial token in script</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script>
const check_report_format = ([reports, observer]) => {
  const report = reports[0];
  assert_equals(report.type, "feature-policy-violation");
  assert_equals(report.body.featureId, "sync-xhr");
  assert_equals(report.body.disposition, "report");
};

promise_test(async t => {
  const report = new Promise(resolve => {
    new ReportingObserver((reports, observer) => resolve([reports, observer]),
                          {types: ['feature-policy-violation']}).observe();
  });

  // Generate token with the command:
  // generate_token.py http://127.0.0.1:8000 FeaturePolicyReporting --expire-timestamp=2000000000
  const trialTag = document.createElement('meta');
  trialTag.httpEquiv = "origin-trial";
  trialTag.content = "ApBWaWympGv9yGwIbWoVDwk25NAT5Zkpfs2nx9PIM0GSXGcLHanrrJQteJgylNk45tun6wJjWUKBZoEsa+BzQgAAAABeeyJvcmlnaW4iOiAiaHR0cDovLzEyNy4wLjAuMTo4MDAwIiwgImZlYXR1cmUiOiAiRmVhdHVyZVBvbGljeVJlcG9ydGluZyIsICJleHBpcnkiOiAyMDAwMDAwMDAwfQ==";
  document.head.appendChild(trialTag);

  const xhr = new XMLHttpRequest();
  xhr.open("GET", document.location.href, false);
  xhr.send();
  check_report_format(await report);
}, "Feature policy report only mode when origin trial token is added by script");


</script>