feature-policy/resources/feature-policy-geolocation.html

<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
<script>
  "use strict";

  Promise.resolve().then(async () => {
    await test_driver.set_permission(
      { name: "geolocation" },
      "granted",
      false
    );
    try {
      await new Promise((resolve, reject) => {
        navigator.geolocation.getCurrentPosition(resolve, reject);
      });
      window.parent.postMessage({ enabled: true }, "*");
    } catch (e) {
      window.parent.postMessage({ enabled: false }, "*");
    }
  });
</script>