Clearkey multi session problem

[TadejZupancic]

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Issue description

I was trying to create a playlist of clearkey videos. I have my own local drm callback, that provides the right key. Single videos played fine. After creating a playlist, I noticed, that local drm callback is called only for the first video and the next ones try to use the same key, which does not work.

Then I've enabled multisession and the application crashed (android.media.MediaDrm$MediaDrmStateException: Failed to set property: Unsupported scheme or data format) at line:
mediaDrm.setPropertyString("sessionSharing", "enable"); in DefaultDrmSessionManager.java

If I comment that line out, everything works fine (drm callback is called for every video in the playlist).

Reproduction steps

Add this to the demo player medialist:
{
"name": "Clearkey",
"uri": "https://dileque.si/test/stream.mpd",
"drm_scheme": "clearkey",
"drm_multi_session": true
}

and set the drmCallback to:

LocalMediaDrmCallback drmCallback = new LocalMediaDrmCallback(
            ("{\"keys\":[{\"kty\":\"oct\",\"k\":\"kUymJmQI24JtIPh1R9qk1A\",\"kid\":\"QUxNQUVTTE9WRU5BMDAwMQ\"}],\"type\":\"temporary\"}").getBytes());

in PlayerActivity's buildDrmSessionManagerV18

Link to test content

Look above.

Version of ExoPlayer being used

2.8.4

Device(s) and version(s) of Android being used

Xiaomi Mi A1 (Android One), Android 8.1

A full bug report captured from the device

Will send it to email.