SDK / exoplayer

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=177011497

Also slightly improve language normalization/documentation.

For this CL, it is assumed that null and "und" languages are different
entities. Once we fully tackle language tag normalization, we can decide
whether to normalize the "undefined" language.

Issue:#2867
Issue:#2980

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=177008509

Guard against out-of-range timestamp

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176997767

A message to stop the playback and to quit the playback thread was posted in release().
The stop message removed all other already queued messages which might include
the second message to quit the thread. That led to infinite waiting in the
release method because the playback thread never got the quit signal.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176997104

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176989632

Update the default AdaptiveTrackSelection and DefaultLoadControl to use playback
speed information.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176989168

currentTimeMillis is not guaranteed to be monotonic and elapsedRealtime is
recommend for interval timing.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176853118

Fixed by explicitly waiting for the timeline update. This shouldn't be
necessary and will be removed as soon as the correct order of events
can be guaranteed (timeline change -> state change -> onSeekProcessed).

The waiting for the timeline update is implemented by introducing the
feature that the test runner also waits until the action schedule has
finished before stopping the test.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176848540

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176837939

In a test run where no exceptions were thrown on the main thread and the test
did not time out, exceptions from onPlayerError were not correctly propagated to
the test thread (handleException would be called with null).

Fix ExoPlayerTestRunner.onPlayerError to propagate the actual exception from the
player.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176825907

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176821463

We've found that in our production environment, the AAC stream's timestamp exceeds the 33bit limit from time to time, when it happens, `peekId3PrivTimestamp` returns a value that is greater than `TimestampAdjuster.MAX_PTS_PLUS_ONE`, which causes a overflow in `TimestampAdjuster.adjustTsTimestamp` (overflow inside `ptsToUs`) after playing for a while . When the overflow happens, the start time of the stream becomes negative and the playback simply stucks at buffering forever.

I fully understand that the 33bit is a spec requirement, thus I asked our stream provider to correct this mistake. But in the mean time, I'd also like ExoPlayer to handle this situation more error tolerance, as in other platforms (iOS, browsers) we see more tolerance behavior.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176768835

This change broke playback through playlists.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176764830

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176763841

Also prevent skip when there's a pending reset, and add a
TODO to split/fix chunk discard and downstream format change
reporting.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176760955

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176759080

This is mostly useful for suppressing the initial position
discontinuity reported by ClippingMediaPeriod.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176758972

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176749136

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176693785

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176666247

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176664332

This brings ClippingMediaSource clip failures in line with
what MergingMediaSource does when it cannot merge.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176660123

It currently always reports 0, but it should report the position
passed through selectTracks. Reporting should also be disabled if
there's a seekToUs call.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176644228

Tests to follow (want to fix breakages first).

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176642610

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176629070

Parse DASH manifest's publishTime node as defined by ISO/IEC 23009-1:2014,
section 5.3.1.2.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176525922

Until recently, changing primary track formats were reported when the
corresponding media chunk was discarded which always happened immediately
after the sample has been read.

Now, media chunks may be discarded later on or in batches, leaving the
current reporting mechanism broken because changes may never be reported.

This fix separates the discarding from the reporting such that format changes
can be reported when the media chunk is first read from, while the discarding
operation only discards without reporting format changes.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176519071

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176515168

Currently EventMessage's presentationTimeMs is kept separately in
EventSampleStream. However, EventMessage's presentationTimeMs maybe used in
other places besides EventSampleStream, such as when handling `emsg' messages
targeting the player. This CL let EventMessage object to holds its
presentationTimeMs for such use cases.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176502938

Fix initializationData check for SSA subtitles

We (eventually - albeit possibly infinitely far in the future)
expect a timeline update with a window of known duration. This
also stops live radio stream playbacks transitioning to ended
state when their tracks are disabled.

As part of this fix, I found an issue where getPeriodPosition
could return null even when defaultPositionProjectionUs is 0,
which is not as documented.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176492024

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176487991

This allows implementations of those classes to take into account the playback
speed for adaptive track selection and controlling when to resume the player.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176484361

Currently testRunner.blockUntilEnded waits for the first transition to
STATE_ENDED or _IDLE before returning. In order to support tests with
player repreparations after one playback finished, this change adds an
option to specifiy the number of expected transitions to ended.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176484047

The ExoPlayerImplInternal.reset method now takes the same set of options
as the ExoPlayer.prepare method. This also allows to
- Remove some code duplication within ExoPlayerImplInternal
- Fix calls to prepare(sameSource, resetPosition=true, resetState=false)
  with enabled shuffle mode where the position was not correctly reset to the
  first period index.
- Keep the current timeline when calling stop (in line with ExoPlayerImpl).

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176481878

The initial period index was counted in onPlayerStateChanged. However, we
actually want to save the period index in the newly introduced onPositionDiscontinuity
after preparation.

While being here, also updated deprecated LinkedList to ArrayList.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176479509

Currently onTimelineChanged doesn't allow to distinguish easily between the
different reasons why it's being called. Especially, finding
out whether a new media source has been prepared or the current source
refreshed dynamically was impossible without tightly coupling the player
operations with the listener.

The new reasons provide this disdinction by either indicating a newly
initialized media source, a dynamic update to an existing timeline
or manifest, or a reset of the player (which usually results in an
empty timeline).

The original onTimelineChanged method without reason is kept in the
DefaultEventListener as deprecated to prevent the need to update all
existing listeners in one go.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176478701