SDK / exoplayer

- This means DrmInitData is propagated through sample queues (i.e.
  is effectively attached to every sample, so we can see when it
  changes when reading from the queue).
- It also allows different DrmInitData per track, which is possible
  in muxed MKV/WebM, and per Representation for DASH, although we
  wont be able to seamlessly adapt in the latter case.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=121821928