Oliver Woodman ff201db981 Allow renderers to pull tracks from multiple sample sources.
This is needed for several use cases:

- ExtractorSampleSource with option to play both embedded and out-of-band
  subtitles.
- HLS multi-audio and out-of-band-webvtt.
2015-08-19 16:33:01 +01:00
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2015-08-04 16:07:54 +01:00