SDK / exoplayer

If an exception is thrown in an IMA callback it crashes the process with lots of
logging from WebView (including several stack traces, etc.). This change wraps
ImaAdsLoader code that might throw, skips any remaining ads (as the errors are
not recoverable, in general) and notifies a new load error callback so that the
application can implement its own handling. The intention is to make the loader
robust to unexpected requests from IMA and avoid crashes.

Also handle IMA loading an ad in an ad group that has no available ads. In rare
cases IMA will try to load an ad for which an error was previously notified, so
this drops those load requests allowing playback of the content to continue.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185985850

Issue:#3340

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185973510

All media periods are part of a queue of windows buffered and played by
ExoPlayer. When repeating windows, the current MediaPeriodId is insufficient
to distinguish between the repetitions of the same period. This makes it hard
to see to which media period load events belong to, and it is also difficult to
determine whether two media periods belong to the same logical window or
whether they are part of different repetitions of the same window.

Therefore this change adds a unique sequence number to each window in the
sequence of windows and this sequence number is saved as part of the
MediaPeriodId.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185829509

If there was no preroll and the pending content position was set before the
first midroll, the pending content position was never cleared so loading the ad
was never triggered.

Only set a pending content position if we know that we need to trigger playing
an ad for the current position and IMA will poll for an ad (because there is a
midroll ad group). Clearing the pending content position happens when IMA pauses
content to play the ad.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185818315

IMA sometimes delivers an ad group load error just after the time of the ad
group, which is problematic now that we set the expected ad group index based on
the last returned content progress.

Only update the expected ad group index once we are within a fixed preloading
threshold of the next ad.

Also fix updating the ad group to use the new ad count, and check for ad group
load errors when we have no expected ad group defensively.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185803086

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185681751

Content progress is only polled if there are midroll ad groups. If the ad tag
had only preroll/postroll ads, the pending content position was not provided to
IMA, which meant that the postroll ad could never play.

Only set the pending content position if there are midroll ads.

Issue: #3715

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185680803

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185676652

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185674707

Issue: #3782

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185673731

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185673454

Issue:#3792

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185668919

This error marks the current ad group as unplayable.

Issue: #3801

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185663472

Also added comments for all existing devices for easier reference.

Issue:#3835
Issue:#3236

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185661900

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