SDK / exoplayer

Expose the input buffer for Exoplayer V2. This allows subclasses to
parse the input buffer before it is decoded. One particular usage
of this is to allow parsing user data stored in the tracks
(e.g. SEI in H264), and incorporate the user data into the rendering.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117865971