LayoutTests/media/audio-playback-restriction-removed-track-enabled.html

<!DOCTYPE html>
<html>
<head>
    <title>audio-playback-restriction</title>
    <script src=media-file.js></script>
    <script src=video-test.js></script>

    <script>

    let audioTrack = null;
    function runTest()
    {
        video = document.getElementsByTagName('audio')[0];

        if (window.internals)
            run(`internals.setMediaElementRestrictions(video, 'RequireUserGestureForAudioRateChange')`);

        waitForEventAndFail('error');
        waitForEvent('canplaythrough', canplaythrough);
        run(`video.src = findMediaFile('video', 'content/audio-tracks')`);
    }    

    function canplaythrough()
    {
        waitForEvent('playing', playing);
        video.audioTracks.addEventListener('change', setMuted, true);
        run('video.play()');
    }

    function playing()
    {
        for (let i = 0; i < video.audioTracks.length; i++) {
            if (video.audioTracks[i].enabled)
                continue;

            audioTrack = video.audioTracks[i];
            break;
        }
        if (audioTrack === null)
            failTest('Failed to find disabled audio track!');

        runWithKeyDown('audioTrack.enabled = true');
    }
    
    function setMuted()
    {
        waitForEventAndFail('pause');
        video.audioTracks.removeEventListener('change', setMuted, true);
        run('video.muted = false');
        setTimeout(endTest, 250);
    }

    </script>
</head>

<body onload='runTest()'>
    <p>Test that when RequireUserGestureForAudioRateChange is set, enabling an audio track with a user gesture clears the restriction.</p>
    <audio muted controls></audio>
</body>
</html>