[general / videojs] Detect callback stream initialization.

[bato3]

Make sure you are using the latest version: run youtube-dl --version and ensure your version is 2018.08.22. If it's not, read this FAQ entry and update. Issues with outdated version will be rejected.

• I've verified and I assure that I'm running youtube-dl 2018.08.22

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If the purpose of this issue is a site support request please provide all kinds of example URLs support for which should be included (replace following example URLs by yours):

• Single video: https://video.sibnet.ru/shell.php?videoid=3422904

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Description of your issue, suggested solution and other information

Is possible detect this initialization way? Now videojs detect only videojsPlayer.src() streams.

var videojsPlayer = videojs('video_html5_wrapper', {
    "controls": true,
}, function() {
    var player = this;
    player.src([{
        src: "/v/743fbceedfc871d4fc3642f5dd67633f/3422904.mpd",
        type: "application/dash+xml"
    }, {
        src: "/v/f5c264f82d20b7fbe0577facb111d01a/3422904.m3u8",
        type: "application/x-mpegURL"
    }, ]);
});