SDK / exoplayer

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118579021

DASH + SS previously had a ridiculously complicated chunk
replacement mechanism in resumeFromBackOff. It also didn't
allow replacement of the first media chunk in the queue,
even though it's possible to remove it in the case that no
corresponding samples have been consumed.

This CL moves DASH + SS to the simpler model used in the
HLS implementation, where the chunk source has a single
opportunity to cancel (and hence later replace) the chunk
when the load error occurs. With this change comes the
ability to replace the first media chunk in the queue in
all cases where it's possible to do so.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118573418

This fixes some nuances with the initial solution. Mainly,
that the TrackStreams returned by selectTrack could not be
used safely until after endTrackSelection was invoked. It
also reduces the need for member variables to track state
between the track selection methods.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118556651

- Use FakeDataSource as the upstream source.
- Actually validate that caching is happening (i.e. reads happen
  on the upstream source only if the data hasn't been read through
  the CacheDataSource already).
- Move FakeClock to sit alongside the other Fake classes.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118555903

In V2 we'll at some point start using DataSource factories
for creating DataSource instances. If there are two DataSource
interfaces this gets unnecessarily awkward.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118470751

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118457489

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118455206

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118040127

This removes the need for each SampleSource implementation to
implement 3x "if(condition) {noop}" tests (ChunkSampleSource
and SingleSampleSource were missing some of these checks).
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118036233

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118032818

This change optimizes startup and track selection for HLS. Changes
in HlsChunkSource avoid unnecessary re-requests for media playlists.
Changes in HlsSampleSource optimize exit from the limbo state (i.e.
when endTrackSelection is first called).
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118026962

1. SampleSource now has an explicit track selection state. This state is entered
   after the source is prepared, and also by calling startTrackSelection.
2. endTrackSelection commits selection changes, and is responsible for doing the
   right thing w.r.t starting/stopping/restarting load operations.
3. All sources now start or restart a load in the case of a new track selection.
   This fixes a problem where a source could be advanced by repeatedly disabling
   and re-enabling whilst paused. Some sources didn't restart a load in this case,
   since the position was unchanged, however the downstream renderer would then
   consume media up to the first keyframe in order to render something. Hence
   each disable/re-enable would advance by a keyframe.
4. This change will enable a subsequent change where we'll discard media for
   non-selected tracks earlier than we do currently (i.e. we'll hook the extractor
   to a dummy track output, so the samples will never be written to a rolling
   buffer). This will enable a further subsequent change where buffer contributions
   are per-renderer rather than per-source.

Issue: #1041
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118024436

Issue: #1387
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118024270

* Do not stop playback onPause but onStop in N and greater.
* Fix back navigation after app has been put to background.
* Make VIEW intent work when PlaybackActitivty is already launched.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118022964

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118021856

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118021575

Issue #1387
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118021498

Issue: #1383
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=118021452

This fixes an issue where the PsExtractor would start reading
unsynchronized if sniff was called.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117958077

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117908518

Expose the input buffer for Exoplayer V2. This allows subclasses to
parse the input buffer before it is decoded. One particular usage
of this is to allow parsing user data stored in the tracks
(e.g. SEI in H264), and incorporate the user data into the rendering.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117865971

Issue: #1263
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117813106

Also use MediaCodec buffer flag constants instead of those on MediaExtractor.

This is in preparation for merging InputBuffer and SampleHolder.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117810136

This version only supports 16-bit uncompressed PCM. A follow-up CL will
add support for other sample bit depths.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117809475

Also hooked up DemoPlayer to ExtractorSampleSource events.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117809051

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117808998

If this situation is encountered, we assume that the encoder has a good reason to
do this and use the last pts + frameDuration as new pts.

Issue: #1295
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117808961

- Remove special DefaultTrackOutput.sampleData method, and have
  SingleSampleMediaChunk use the regular one instead.
- Make DummyTrackOutput behave correctly is allowEndOfInput is
  false.
- Simplify progress tracking in ExtractorSampleSource.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117808659

This is the first version and is still not linked to the WebVTT parser nor
does it support all the intended features, but it was left this way to
ease the review a little bit.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117722492

As per: http://developer.android.com/training/articles/perf-tips.html
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117716743

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117701759

Fixed issue in which unknown sample mime types would cause MediaPresentationDescription to throw an NPE.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117560114

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117558066

When showing a track selection for a renderer, the override
variable could end up being retained from some previous call
to show a track selection for some other renderer.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117557994

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117544932

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117543706

- Not doing any renaming for now. It'll be easier to wait
  until after the extensions themselves are brought across.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117438338

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117338990

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117338865

Based on

http://docs.oracle.com/javase/specs/jls/se7/html/jls-9.html#jls-9.3
http://docs.oracle.com/javase/specs/jls/se7/html/jls-9.html#jls-9.5
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=117338783