SDK / exoplayer

* Add `setOutputStreamOffsetUs(long)` method in `AudioSink`.
* Add private methods `setOutputStreamOffsetUs(long)` method in `MediaCodecRenderer` and `DecoderAudioRenderer`.
* Add protected method `onOutputStreamOffsetUs(long)` method in `MediaCodecRenderer`, in which:
  * `MediaCodecRenderer` itself will be no-op for this method.
  * `MediaCodecAudioRenderer` will propagate this value to its `audioSink`.
* Add logics in `DecoderAudioRenderer` to calculate `outputStreamOffsetUs`.

PiperOrigin-RevId: 479265429
(cherry picked from commit 4c732410)