olly 2b13165738 Optimize HLS seeking.
I think the concept of a sparse track might need formalizing
in Format at some point. We should probably do a similar thing
with sparse tracks in ExtractorSampleSource as well. WDYT?

Issue: #551
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=120530195
2016-06-15 19:39:10 +01:00
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2016-06-15 19:39:10 +01:00