LayoutTests/http/tests/permissions/permission-status-onchange-event-window.html

<!DOCTYPE html>
<html>
<head>
<script src="/resources/js-test-pre.js"></script>
<script src="/resources/notifications-test-pre.js"></script>
</head>
<body>
<script>

description("This test checks that the Permissions API on-change event works in window contexts.")

jsTestIsAsync = true;

navigator.permissions.query({ name: "geolocation" }).then((permissionStatus)=>{
    permissionStatusState = permissionStatus.state;
    shouldBeEqualToString("permissionStatusState", "prompt");

    onChangeCalled = false;
    permissionStatus.onchange = () => {
        permissionStatusState = permissionStatus.state;
        shouldBeEqualToString("permissionStatusState", "granted");
        onChangeCalled = true;
    };

    testRunner.setGeolocationPermission(true);
    shouldBecomeEqual("onChangeCalled", "true", () => {
        finishJSTest();
    });
});

</script>
<script src="/resources/js-test-post.js"></script>
</body>
</html>