SDK / exoplayer

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=110768506

This CL is prepares the ground for refactoring the Webvtt parser,
so as to use the common parsing algorithms in both parsers. In order
to do this, the Webvtt Parser will be refactored. As a side note, many
more test cases will be added once the new subtitle features are
implemented. Some useful test cases have also been left for a following
CL, to allow an easy code review.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=110466914

Seems (marginally) nicer than making one up :). I didn't
realize there was a method that didn't require a framerate
to be passed!
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=110456874

Improve identification of (E)AC3 content in MPEGTS and tweak EAC3 parsing

This allows implementation and injection of custom MediaCodecSelector
instances. By injecting a custom selector, it's possible for applications
to exert more control over which decoder(s) they instantiate. For example,
applications can force use of a software decoder.

GitHub Issue #938
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=110369810

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=110238340

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=110231626

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=110155932

Issue: #1068
Issue: #1001

blacklisted broken mp3 decoder on api lower than 20

when the dataSource reaches to the end.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=110131793

Issue: #689
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=110003312

Fix behavior of getTimeUs when seeking after the last entry in the table of
contents. Round correctly in getPosition, clipping to the stream duration based
on the input length (if known), falling back to the stream size from the header.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=109993852

Multiple identical TTML fontStyles or fontWeights or textDecorations
on the content for a specific moment were rendered as if there's only
one decoration (span).
That's because SpannableStringBuilder.setSpan(span, start, end, flag)
found an earlier set span (the static allocated span's reference
is the same each time) and only refreshed this first span's start and
end values instead of adding a new span at its (new) different range.
This patch removes the static data members;
this makes the newly allocated span objects distinguishable.
A correct implementation is favoured over worries about memory
consumption.

Issue: #1038
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=109906628

This is a no-op change that just makes the definitions consistent
with the H264 ones, for general neatness/consistency reasons.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=109892547

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=109851975

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=109832096

Allow multiple identical but intermittent spans

Multiple identical TTML fontStyles or fontWeights or textDecorations
on the content for a specific moment were rendered as if there's only
one decoration (span).
That's because SpannableStringBuilder.setSpan(span, start, end, flag)
found an earlier set span (the static allocated span's reference
is the same each time) and only refreshed this first span's start and
end values instead of adding a new span at its (new) different range.
This patch removes the static data members;
this makes the newly allocated span objects distinguishable.
A correct implementation is favoured over worries about memory
consumption.

Issue: #1038
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=109906628

This is a no-op change that just makes the definitions consistent
with the H264 ones, for general neatness/consistency reasons.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=109892547

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=109851975

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=109832096