function runTest(config) {
    // When the sandbox attribute is present on an iframe, it will
    // treat the content as being from a unique origin. So try to
    // call createMediaKeys() inside an iframe and it should fail.

    function load_iframe(src, sandbox) {
        return new Promise(function (resolve) {
            var iframe = document.createElement('iframe');
            iframe.onload = function () {
                resolve(iframe);
            };
            iframe.sandbox = sandbox;
            iframe.src = src;
            document.documentElement.appendChild(iframe);
        });
    }

    function wait_for_message() {
        return new Promise(function (resolve) {
            self.addEventListener('message', function listener(e) {
                resolve(e.data);
                self.removeEventListener('message', listener);
            });
        });
    }

    promise_test(function (test) {
        var script = 'data:text/html,' +
          '<script>' +
          '    window.onmessage = function(e) {' +
          '        navigator.requestMediaKeySystemAccess("' + config.keysystem + '", [{' +
          '           initDataTypes: [\"' + config.initDataType + '\"],' +
          '           audioCapabilities: [' +
          '               { contentType:\'' + config.audioType + '\'},' +
          '           ]' +
          '       }]).then(function(access) {' +
          '            return access.createMediaKeys();' +
          '        }).then(function(mediaKeys) {' +
          '            window.parent.postMessage({result: \'allowed\'}, \'*\');' +
          '        }, function(error) {' +
          '            window.parent.postMessage({result: \'failed\'}, \'*\');' +
          '        });' +
          '    };' +
          '<\/script>';

        // Verify that this page can create a MediaKeys first.
        navigator.requestMediaKeySystemAccess(config.keysystem, [{
            initDataTypes: [config.initDataType],
            audioCapabilities: [
                {contentType: config.audioType},
            ]
        }]).then(function (access) {
            return access.createMediaKeys();
        }).then(function (mediaKeys) {
            // Success, so now create the iframe and try there.
            return load_iframe(script, 'allow-scripts')
        }).then(function (iframe) {
            iframe.contentWindow.postMessage({}, '*');
            return wait_for_message();
        }).then(function (message) {
            assert_equals(message.result, 'failed');
        });
    }, 'Unique origin is unable to create MediaKeys');
}