DemoPlayer moves into core library as SimpleExoPlayer, which
implements ExoPlayer.
Issue: #383
Issue: #592
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=123090184
Allows the user to provide their own criteria for selecting one of the available tracks
without having to reimplement the track assignment logic, i.e. linking type x tracks with
type x renderer.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=122422087
prepare(SampleSource) is renamed to setSource(SampleSource). The player
immediately transitions to STATE_BUFFERING when the source is set, at which
point doSomeWork is called.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=119838825