SDK / exoplayer

Fixes the following issues:

1. When a surface is set, it's expected that the renderer will
notify video size + when a frame is rendered to it. This is true
even if the surface isn't changing. Right now this is achieved
by setting renderedFirstFrame to false, but this is problematic
in the case that the surface isn't changing because (a) it will
force rendering of a subsequent frame to the output even when
paused, which is incorrect, and (b) isReady will return false
until this occurs.

2. When the surface really is changing, isReady can return false
until the first frame has been rendered into the new surface, which
will break seamless surface switching. This change allows isReady
to return true up to allowedJoiningTimeMs for this case.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=154171111

* colorSpace, colorRange and colorTransfer are relevant to all videos.
* The rest of the fields are relevant only to HDR videos.
* Tested on a prototype device that decodes VP9 profile 2, 10 bit.
* The Webm spec spells color as 'colour' so the webm id reference use the same spelling.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=154098189

This prevents illegal casts.

Issue:#2702

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=154078240

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=154077149

Prior to this change, the only way to switch SimpleExoPlayerView
was to do:

oldView.setPlayer(null);
newView.setPlayer(player);

This would cause the video renderer to have to transition through
oldSurface->noSurface->newSurface, which is inefficient (noSurface
requires platform decoders to be fully released).

After this change we support:

newView.setPlayer(player);
oldView.setPlayer(null);

This results in direct oldSurface->newSurface transitions, which are
seamless on Android M and above. The change also adds some robustness
against developers ending up with strange behavior as a result of
clearing the player from a view in a different ordering than we expect
w.r.t. registering of other listeners.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=154044976

Issue: #2501

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=154036726

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=153858804

Added mp3 support to FLV extractor

Fix potential OOM that can occur reading first NAL packet before seq header

Simplify cross-compiling on Mac OS X host machine by copy-paste commands

Allow out of tree builds.

This is a no-op cleanup change.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=153830409

Issue: #2680

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=153827243

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=153762476

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

Remove unnecessary check. sampleRateIndex is masked with 0x03 so it is constrained to be between 0 and 3.

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