SDK / exoplayer

At the end of playback, BufferProcessors need to be drained to process all
remaining data, then the output needs to be written to the AudioTrack before
stop() is called.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148339194

Clarify naming for ClearKey DRM support

Added support for CENC ClearKey

This allows the TsExtractor to automatically determine the
closed caption tracks to expose by parsing available
descriptors.

Issue:#2161

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148321380

Issue: #2486

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148217936

Issue: #2362
Issue: #2176

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148216614

This allows BufferProcessors to partially and/or asynchronously handle
input/output. Document contract for queueInput and getOutput.

Update ResamplingBufferProcessor to use the new interface.

Separate submitting bytes vs. writing data to the AudioTrack.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148212269

Issue:#2161

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148203980

This CL allows passing multiple formats describing CC channels to the
TS payload reader factory. As a simple usecase, ATSC can expose both
608 channels by passing a two element list with the corresponding
accessibility channels. The HLS media source can construct this list
from the EXT-X-MEDIA:TYPE="CLOSED-CAPTIONS" tags, including language
and selection flags. The interface extends without modification to
708.

Pending work:
* Multiple CC channels in HLS.
* caption_service_descriptor parsing for overriding the user's selection.
* 708 support in SEI reader.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148030293

Issue #2176

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148027655

This avoids breaking the player if the first variant is not
supported by the device.

Issue:#2353

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148025791

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148024082

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=148018580

Updated Gradle, Compile and Build Tools Version

Add Flags to MP3 Extractor to force CBR Seeker

Added flags to the mp3 extractor to control behavior of the extractor. Added FLAG_ENABLE_CONSTANT_BITRATE_SEEKING to let the extractor know that the CBR seeker is desired in the case where the seeker has determine the track is not seekable For example, in the case where the track has a Xing Header but no content table.

InitializationChunk calls init(null). When the initialization and index data is separate they need to
be loaded separately which results to two init(null) calls.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=147837985

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=147833328

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=147796398

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=147794314

Issue #2462

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=147731351

Fixed a typing error

Make DrmSessionException constructor public to enable creating custom DrmSessionManager implementations.

Issue: #2386

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=147725616

Make DrmSessionException constructor public to enable creating custom DrmSessionManager implementations.