SDK / exoplayer

Before modularisation of the code, it was possible to do an out of tree build
giving an -PbuildDir=someDir argument to gradle. With the modularisation, it's
broken as using -PbuildDir=someDir will force the same directory for each
projects, which breaks the gradle build system.

This commit adds a new externalBuildDir project property to allow out of tree
builds again. When set, it updates the buildDir property for each project to
point to ${externalBuildDir}/${project.name}. That way, the build artifacts are
written in the out of tree directory in a project specific folder.

To do an out of tree build, use

    gradle -PexternalBuildDir=someDir ...

It supports absolute and relative path. Relative path are interpreted against
the ExoPlayer root directory.

When calling CronetDataSourceFactory.createDataSourceInteral, a null pointer
is passed as clock to the CronetDataSource constructor which in turn throws a
NullPointerException. Can be prevented by using other constructor without
clock parameter.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=153470874

This class is unnecessary; you can simply pass a thread
priority to HandlerThread's own constructor. It's also
broken, since HandlerThread.run() immediately overrides
the priority being set!

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=153461225

- Update relevant documentation
- Use individual modules for the demo app. Given it's
  preferable to use them over the full library, and that
  many people probably use the demo app as a starting
  point, we should set the right example even though we
  currently need to include all of them.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=153454898

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=153453768

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=153446615

Issue: #2675

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=153445372

If AudioTrack.setPlaybackParameters was called before initialization (for
example, when an audio renderer is enabled) the parameters would actually be
dropped, because configure calls reset, which didn't apply draining playback
parameters if the track was not initialized. It would then overwrite the
draining parameters with the current parameters.

Set the playback parameters directly (without draining) for uninitialized tracks
so that the call to setPlaybackParameters in configure is a no-op.

Also, reset the stored channel count and sample rate when the audio processor
is released so that configure returns true when it is next used, which makes
sure that it gets flushed.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=153078759

The draw method checks if all inputs are the same as in the previous call.
The options to strip the subtitle of its styles were applied each time,
in order to check if the final CharSequence is still the same.

This additional computation (and memory allocations) can be prevented by
checking if the original CharSequence (including all styles) and the
flags to remove those styles are the same. The actual style removal is now
part of setupTextlayout().

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=153061064

Issue: #2454

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152938743

The track initialization data of Tx3g includes default style values for
font styles, colour, and font family. Additionally the decoder now supports
vertical subtitle placements other than the Tx3g default of 85% video height.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152930057

*** Reason for rollback ***

The force submit broke GVR: []

*** Original change description ***

Add DashDownloaderService which downloads DASH streams at the background

***

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152877808

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152815185

The idea of using reflection was so that a developer could
delete a package they didn't want and have everything else
still compile. However, a developer doing this is likely
building from source, in which case editing the factories
too is pretty trivial.

Removing the reflection makes specifying extractor flags
via the default factory easy, and removes the need for
special proguard config.

Issue: #2657

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152810423

Extended Tx3gDecoder to read additional information after subtitle text.
Currently parses font face, font size, and foreground colour.

Font identifier and other information provided in subtitle sample description
not yet supported.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152793774

When no video tracks or renderers are present, attempt audio adaptation.

Issue:#1975

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152708422

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152708351

I've also removed unnecessary "empty" cases, since to add them
everywhere would bloat the code quite a lot. Note that
new String(new byte[0], 0, 0, encoding) is valid and will produce
and empty string.

Issue: #2663

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152697288

Adding the default branch prevents linting warnings.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152675789

This allows propagating format changes to the track output.

Issue:#2552

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152672983

Also fix an issue where ad timelines with unknown ad period durations
would not be shown in multi-window mode. (The time bar doesn't use the
duration of ad periods, but shows a fix-size indicator instead.)

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152666055

ExoPlayerImpl.prepare() replaces the timeline with an empty timeline. After this
happens, MSG_SOURCE_INFO_REFRESHED could be handled on the main thread and
could relate to the old source, so the player could expose a stale timeline.

Count pending prepares in ExoPlayerImpl so that source info refreshes can be
suppressed until preparation actually completes.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152496255

Issue: #2582

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152494408

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152492104

When option is set to false, SubtitlePainter strips all absolute
and relative font size spans from the cue text.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152484724

- Removed the PES_STRIPPED flag. It's unnecessary. We can strip
  PES in the TS extractor instead.
- Made nearly all of the object classes in DvbParser immutable.
  Else it's non-obvious that none of this state can be mutated.
- Made a a lot of the methods in DvbParser static for the same
  reason.
- Removed unnecessary null checks, code that was never executed,
  unused fields etc.
- Add proper flushing of DvbParser, to prevent corrupt output
  following a seek.

Merge branch 'dev-v2-dvbsubs' of git://github.com/tresvecesseis/ExoPlayer into tresvecesseis-dev-v2-dvbsubs

Solved by adding saving reference to previous TrackGroup. Toast only displayed
after TrackGroup changed.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152242954

Also add instructions for building arm64-v8a and x86.

Issue: #2561

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152141270

Only enable multi-window mode when the duration of every period in the timeline
is known. Also, remove the warning logged when there are too many windows as it
doesn't add much.

The player's current period index was not masked while there were
unacknowledged seeks. This led to the displayed position jumping, between when
seekTo was called (after which the position would be masked but not the period
index) and the seek being acknowledged (at which point the time bar's position
would jump back to the seek position, due to the period index being resolved).
Mask the period index, like the window index, to fix this behavior.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152116040

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152107538

This allows custom parsers to be used.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152005477

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152003529

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=151994281

Opus: use fixed max size in Opus decoding

Disables codecIsAdaptive for Odroid-XU4