chromium/third_party/blink/web_tests/media/encrypted-media/encrypted-media-setmediakeys-multiple-times-with-the-same-mediakeys.html

<!DOCTYPE html>
<html>
    <head>
        <title>setMediaKeys() multiple times with the same MediaKeys.</title>
        <script src="encrypted-media-utils.js"></script>
        <script src="../../resources/testharness.js"></script>
        <script src="../../resources/testharnessreport.js"></script>
    </head>
    <body>
        <video></video>
        <script>
            promise_test(function(test)
            {
                var video = document.querySelector('video');
                var content = '../content/test-encrypted.webm';
                var mediaKeys;

                assert_equals(video.mediaKeys, null);

                return navigator.requestMediaKeySystemAccess('org.w3.clearkey', getConfigurationForFile(content)).then(function(access) {
                    return access.createMediaKeys();
                }).then(function(result) {
                    mediaKeys = result;
                    assert_not_equals(mediaKeys, null);
                    // Set mediaKeys on video should work.
                    return video.setMediaKeys(mediaKeys);
                }).then(function() {
                    assert_true(video.mediaKeys === mediaKeys);
                    // Set mediaKeys on video again should return a resolved
                    // promise.
                    return video.setMediaKeys(mediaKeys);
                }).then(function() {
                    assert_true(video.mediaKeys === mediaKeys);
                    // Load the media element to create the WebMediaPlayer.
                    video.src = content;
                    // Set mediaKeys again on video should still return a
                    // resolved promise.
                    return video.setMediaKeys(mediaKeys);
                }).then(function() {
                    assert_true(video.mediaKeys === mediaKeys);
                });
            }, 'setMediaKeys() multiple times with the same MediaKeys.');
        </script>
    </body>
</html>