SDK / exoplayer

Also make ad group skipping more robust. After calling onError for an ad, IMA
will sometimes trigger an ad group load error, so this needs to be handled in a
way that allows some ads to be loaded already for the ad group.

This change also fixes calculation of the expected ad index to take into account
whether the position is being faked to trigger loading an ad or is the actual
player position.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185655844

Releasing the player released the internal playback thread once renderers were
released. Releasing a MediaPeriod queued a Loader.ReleaseTask on the loading
thread which would post back to the playback thread. If the playback thread had
been quit by the time this happened, the release task wouldn't be run.

Release on the loading thread instead of the playback thread. This avoids
needing to block releasing the player until the loading threads have ended, and
ensures that release tasks will run eventually. As part of this change,
ExtractorMediaPeriod's call to Extractor.release will now run on the loading
thread (which means that all Extractor methods are called on that thread) and
other cleanup in ReleaseCallback will run on the loading thread instead of the
playback thread.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185651320

Issue: #3724

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185548632

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185526653

Issue:#3835

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185501181

IMA's cue points may not be in order, so sort them. It looks like IMA events use
time ordered ad indices, so it is not necessary to map between the original cue
point order and the time order.

Issue: #3716

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185495798

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185409304

There are 4 tests which can't currently be moved:
 - DownloadManagerTest explicitly uses the main looper which isn't easily
   supported because the test runs on this thread.
 - ContentDataSourceTest uses an AssetFileDescriptor which wraps a
   ParcelFileDescriptor. It seems Robolectric doesn't correctly forward the
   inner wrapped file descriptor leading to NPE.
 - CacheContentIndexTest and SimpleCacheSpanTest both work fine with Gradle
   but fail with seemingly valid test failures on Blaze.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185366678

This is requested for Romanian translation.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185359071

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185139106

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185138158

Removed option to pass null keys parameter.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185134822

If the period uid doesn't match, the update procedure currently doesn't
remove the correct periods. This may cause the player to get stuck or to play
the wrong periods.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185129503

Issue:#3816

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185124378

Device models are from
https://support.google.com/googleplay/answer/1727131?hl=en. It looks like among
these devices Build.MANUFACTURER can be set to either "PHILIPS" or "Philips",
based on looking at internal bug reports.

Issue: #3807

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185121182

DownloadNotificationUtil should not use getData().

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185002149

We now build one .so file for the opus extension in the
internal build, so make the external build work the same way.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184962896

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184844870

Allow skipping an ad group when requested by IMA, even if we aren't currently
playing one, to handle cases where no ads in an ad group will load (so IMA
requests resuming content but we never managed to start playing an ad).

Use the known ad group index (rather than the expected one) when handling ad
group load errors. This ensures we skip the right ad group if we notify IMA of
playback errors for every ad in the ad group, then IMA notifies that the ad
group is empty via a load error.

Also make some other miscellaneous small fixes to ads code:

- Avoid warning about unexpected ad group indices more than once.
- Output a warning if the ad count in an ad group decreases.
- Remove unnecessary assertion.
- Fix getting the ad duration for ad indices that haven't loaded yet.
- Allow setting an ad group state to its current value.
- Fix javadoc for setting the ad resume position.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184831495

The ad index in the ad group may need to skip over ads that failed to load, so
it can't just be incremented any more.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184812556

When using cronet data source, calling read after the end of input has
been read will trigger this.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184667794

This feature is supported in the ConcatenatingMediaSource and is easily copied to this
media source. Also adding tests to check whether the atomic property works in normal
concatenation and in also in nested use.

Also fixes a bug where timeline methods of the DeferredTimeline were not correctly
forwarded.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184526881

This could happen when a media source is removed from a
DynamicConcatenatingMediaSource and one of its media periods is still active.
This media period is only removed by the player after the player received
a timeline update and thus we shouldn't release the removed child source
as long as it has active media periods.

Issue:#3796

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184522836

If IMA loads an empty VAST document for an ad group it notifies via a LOG
AdEvent. Handle the event by updating the AdPlaybackState accordingly.

The error state will be handled in ExoPlayerImplInternal in a separate change.

Issue: #3584

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184516585

Resolve the media period for ad playback when resolving a subsequent period and
when receiving a timeline where the playing period in range (but wasn't before).

Fix the seek position calculation when a current ad must be skipped and is
followed by another ad.

Check MediaPeriodInfos match when checking MediaPeriodHolders, to handle cases
where a future ad should no longer be played. This may involve playing two
content media periods consecutively.

Issue: #3584

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184514558

DefaultExtractorInput.SCRATCH_SPACE buffer is used to skip data by
reading it into this buffer and discarding.

Simultaneous use of skip methods corrupts this buffer. Normally the
read data is discarded so it doesn't matter but the underlying
DataSource may use the buffer too. If it's a CacheDataSource it uses
this buffer to read data from upstream then write to cache.

Issue: #3762

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184502170

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184501752

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184317120

This avoids reading a format that is not equal because of switching between
NO_VALUE and 0.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184298076

This makes assertion errors in code running on the Looper less easy to miss.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184294290

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184274139

This should be a no-op change.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184150266

For below API level 16, the logic copied from ConnectivityManagerCompat.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184131406

Only filter HlsMasterPlaylists.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=183394956

Helper class to create notifications for downloads using DownloadManager.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=183225948

Issue: #2643

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184844484

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184125114

Even if a developer synchronizes every method, thread safety is still not guaranteed
because the internal callback methods can't be synced from outside.

Issue:#3773

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184122072

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184122057

1. Add string for STATE_CANCELED. Lint doesn't like that the
   switch statement on the state IntDef doesn't have a case
   for STATE_CANCELED. May as well add one, even if we're not
   planning on our demo app showing notifications for this
   state.
2. Replace non-human-readable error message with one provided
   by ErrorMessageProvider.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184120892