SDK / exoplayer

- Centralise compileSdkVersion, targetSdkVersion and
  buildToolsVersion in a single place for gradle.
- Bump compileSdkVersion and targetSdkVersion to 24.
- Bump com.android.tools.build version to re-enable
  instant start.
- Bump targetSdkVersion in manifests (needed for
  internal builds).
- Use standard expandable_list_item from Android in
  the demo app, since ours doesn't look right when
  targeting API level 24. We were also setting the
  theme on the wrong element in the manifest, so I'm
  removing that line.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131929216

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131853683

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131843222

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131825185

Issue:#1772

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131812670

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131810070

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131731376

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131715194

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131714051

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131696858

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131693969

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131693379

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131692317

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131534334

- The need to pass a Clock is pretty much only for testing, so
  make the constructor that takes one package private + use
  the system clock for public constructors.
- Add default timeout values.
- Also make sure we set Content-Type in all license requests,
  since when using Cronet the stack requires it to be set.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131404298

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131398594

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131398162

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131394778

This is done through the bitstream id field and allows removing
the isEac3 parameter from the constructor.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131393477

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131393395

Issue: #1774

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131389528

Defined in ATSC Standard: Digital Audio Compression (AC-3, E-AC-3).
Link: http://atsc.org/wp-content/uploads/2015/03/A52-201212-17.pdf.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131294260

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131294029

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131291816

Tweak Demo app code to facilitate overriding Application methods and change the used DataSourceFactory.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131288634

If they're omitted, it's reasonable to assume it's because
they were uninteresting (i.e. sample data always tightly
packed at the start of the mdat). This is an issue for some
SmoothStreaming streams.

We actually already play such streams successfully, but
that's only due to another bug to be fixed in a following CL.
The same is true for V1, but given the low impact nature,
the fix will be V2 only.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131191975

If currentTrackBundle is updated at the start of the
block and then something goes wrong in the middle (e.g.
one of the skipFully calls) then the extractor wont
resume from the correct place.

This would be caught by our extractor tests if we had
a test sample that requires skipping to the sample data.
I'll try and construct one of those.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131191174

- The -1 needs to be a 0. My bad.
- Create AAC CSD if not defined in manifest, like in V1.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131190995

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131183033

Also tweak how the null checks happen in a few DataSource
implementations (should be no-op changes, but allow you
to look at close() and be happy it does the right thing
without having to loop at the open() implementations).

Issue: #1759

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131172427

There's still some internal to clean up to do, and in particular
it remains a TODO to be able to handle seek calls before the
timeline is set (for this CL, such calls are dropped). This change
does however finalize the API.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131171318

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131164881

Fix the calculation of the seek window for multi-period DASH.

Snap the default initial position back to the start of its segment, to ensure
that the first sample provided when transitioning to a DASH live source is a
key-frame.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131052912

- Remove playingPeriodEndPositionUs. It doesn't look like it's
  required.
- Rename time variables to make it clearer what they are.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131027164

Window is potentially confusing with Android's Window class.
Once Window is renamed, it makes sense to rename Timeline too.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=130938392

Also inline a few methods/classes where they can be made
private and therefore be removed from the public API.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=130935090

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=130933435

Mainly, this allows the extractor to expose multiple audio tracks.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=130928152

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=130922558

Issue: #1754

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=130780466