SDK / exoplayer

The test prepare_withSupportedTrack_playsTrackUntilEnded

- sets up the supported AAC track with the RTSP server;
- uses RtpPacketTransmitter to send RTP packets from the server to the client;
- runs the player until the playback has ended, and
- asserts on the data RTSP has received and queued to the SampleQueue.

In the test, it was necessary to create a FakeUdpDataSourceRtpDataChannel. The
reason we cannot reuse TransferRtpDataChannel is, we rely on BlockingQueue.poll
timeout to identify the end of an RTSP stream, but the time out mechanism is
unstable in Robolectric. For example, when the timeout is set to 8,000 ms, the
actual timeout occasionally happens after 2,000,000 ms (in FakeClock).

PiperOrigin-RevId: 380528710