SDK / exoplayer

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

This causes the player to report that it's started loading
when in the ended state.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176371892

- Properly report internal discontinuities
- Add DISCONTINUITY_REASON_SEEK_ADJUSTMENT to distinguish
  seek adjustments from other internal discontinuity events

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176367365

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176366693

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176366471

Remove an assertion that there was a call to pause content between two
content -> ad transitions.

Also, only use the player position for resuming an ad on reattaching if the
player is currently playing an ad, in case IMA pauses content before the player
actually transitions to an ad.

Issue: #3430

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176365842

Currently for a DASH ChunkSource that consists of multiple sub-streams, we
always use a CompositeSequenceableLoader, which only allows the furthest behind
loader or any loader that are behind current playback position to continue
loading.
This changes allow clients to have more flexibility when deciding the loading
strategy:
- They can construct a different kind of composite SequenceableLoader from
the sub-loaders, and use it by injecting a different CompositeSequeableLoaderFactory accordingly.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176363870

Issue:#3478

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176351086

Issue: #2465

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176341309

This class implements MediaClock itself and handles the switching between
renderer and standalone media clock.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176340615

In particular this allows to have the workaround for
https://code.google.com/p/dexmaker/issues/detail?id=2 in one place only.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176340526

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176337058

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176335667

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176333544

Add Builder pattern to SingleSampleMediaSource and mark existing constructors as
deprecated.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176332964

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176154160

- MediaSourceTestRunner aims to encapsulate some of the logic
  currently used in DynamicConcatenatingMediaSourceTest, so it
  can be re-used for testing other MediaSource implementations.
- The change also fixes DynamicConcatenatingMediaSourceTest to
  execute calls on the correct threads, and to release handler
  threads at the end of each test.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176117535

This test seems to obtain a timeline from a prepared
FakeMediaSource, but that's identical to the timeline
passed into that source to start with :).

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176117133

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176102179

This is helpful for tests which don't care about detailled timeline set-ups
besides the number of windows.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176097369

Add Builder pattern to ExtractorMediaSource and mark existing constructors as
deprecated.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=176088810

This change makes sure progress is being made before reporting
a discontinuity. Else in cases like having no network and
playing a live stream, we allow the discontinuity to be read
each time an internal retry occurs, meaning it gets read
repeatedly. This does no harm, but is noisy and unnecessary.

We should also not allow skipping whilst there is a pending
reset or discontinuity notification, just like we don't allow
reads.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=175953064

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=175940553

Also switch from using MIME types to C.ENCODING_* encodings in DefaultAudioSink.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=175936872