SDK / exoplayer

Also fix possible repeat-preparation for HlsTrackStreamWrapper
and ExtractorSampleSource.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=126640380

At a high level, everything that we need to load in sync
with anything else now implements a new SequenceableLoader
class. This includes ChunkTrackStream, since multiple
demuxed tracks in DASH/SS need to be loaded in sync with
one another. At a higher level, SampleSources are also
SequenceableLoaders, which allows them to be kept in sync
by MultiSampleSource.

CompositeSequenceableLoader is able to load multiple
instances SequenceableLoaders in sync with one another,
and is used in various places where this is required.

This change also removes LoadControl registration, which
was complicated and error prone.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=126632861

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=126631393

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=126622342

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=126324788

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=126306436

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=126286809

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=126202210

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=126196431

This is causing getTrackIndex to fail for live playbacks.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=126189387

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=126175948

- Removes the load delay that was previously present after
  source preparation.
- Prevents premature failure in the case that the buffering
  source fails to prepare.
- SampleSource.Callback will get a second method in a
  subsequent CL, approximately meaning "tell me if I can load
  more stuff". This will remove the need for LoadControl and
  the complexity that comes with it.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=126172573

This is required for buffering to work properly across
playlist transitions. It's also much simpler, since
specifying the buffering policy becomes independent of
the type of media being played (i.e. the source).
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=126051755

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125951381

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125698923

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125691172

1. The readiness of the timeline is only relevant if there
   aren't any enabled renderers. It's also only ready if
   the source after the playing source is actually prepared
   (if not, we're waiting for preparation).
2. Prevent early transition to the ENDED state when the
   playback position hits the duration, but we're not at the
   final entry in the playlist.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125685193

- Always continue loading if we've got less than the minimum
  amount of media in the buffer.
- Use LoadControl in ExtractorSampleSource.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125679669

- Update playbackInfo duration/position/bufferedPosition in a
  single place.
- Remove sampleSource variable, and remove side effects from
  getSampleSource. There was actually a subtle bug where
  getSampleSource wasn't called by anything where no renderers
  where enabled (meaning the source never transitioned).
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125676540

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125670965

Also, getBufferedPosition shouldn't be called if no tracks
are selected.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125670213

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125669080

Also do some naming cleanup + do ms->us seek conversion
in ExoPlayerImpl, since that's where we now do all the
conversions coming out of the player.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125662973

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125661172

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125659817

Issue: #1332
Issue: #1101
Issue: #1083
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125659191

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125658752

Pretty sure this does the same thing.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125581858

The outer class should only deal with the enabled renderers.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125579652

ExoPlayer.EventListener.onPositionDiscontinuity is notified during seeking and
transitioning from one source to the next.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125578976

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125476407

This CL only provides checks for HEVC codecs and adds codec information to Format
instances in DASH. Right now, we check that the supported profiles are advertised
individually and that the supported level is equal or higher than the requested codec
level.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125470489

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125454697

Now it needs to be 2.1.2 to support instant run.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125445366

We have our snazzy new file-based extractor tests now,
and the other ones have historically proven way more
hassle than they're worth (e.g. I spent a good few hours
once just trying to work out how to fix the Mp4 extractor
test, having established it was the test and not the
code that was broken!).

I think some more can go from the ogg package, but leaving
in place for now because it's a bit less clear what to
get rid of.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125330072

skipToNextPage() isn't necessary anymore.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=125147444

- AllowedVideoJoiningTimeMs must be set to 0 for tests so
  that tests which disable/enable video renderers don't
  register a large number of dropped frames.
- Fixed a threading issue that could cause occassional test
  failure.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=124978843

The ones that are commented out are legitimately broken
and will need a library fix.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=124978438

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=124976833