andrewlewis 45bc4a0374 Pass player and isTopLevelSource to MediaSource.prepareSource.
These additions are useful for sources that need to track the playback position
and control playback.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=140828310
2016-12-02 19:23:35 +00:00
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2016-11-25 20:18:32 +00:00