SDK / exoplayer

* Prevents calling endTracks() before all PMTs have been
  processed.
* Adds a unique ID to the format of each track. This allows
  the track selector to identify which track belongs to
  each program. The format of each id is
  "<program number>/<track output id>".

Note: This CL will break malformed TS files whose PAT
declares more PMTs than it actually contains, which
previously were supported. This does not apply for HLS
mode.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=146151642