Pulling libwebm from upstream

Changes from upstream:
249629d make Mkv(Reader|Writer)(FILE*) explicit
7f3cda4 mkvparser: fix a bunch of windows warnings
5c06178 Merge "clang-format on mkvparser.[ch]pp"
4df111e clang-format on mkvparser.[ch]pp
7b24501 clang-format re-run.
c6767b9 Change AlignTrailingComments to false in .clang-format
9097a06 Merge "muxer: Reject file if TrackType is never specified"
eddf974 Merge "clang-format on mkvmuxertypes.hpp and webmids.hpp"
def325c muxer: Reject file if TrackType is never specified
41f869c Merge "clang-format on webvttparser.(cc|h)"
fd0be37 clang-format on webvttparser.(cc|h)
207d8a1 Merge "clang-format on mkvmuxerutil.[ch]pp"
02429eb Merge "clang-format on mkvwriter.[ch]pp"
0cf7b1b Merge "clang-format on mkvreader.[ch]pp"
2e80fed Merge "clang-format on sample.cpp"
3402e12 Merge "clang-format on sample_muxer.cpp"
1a685db Merge "clang-format on sample_muxer_metadata.(cc|h)"
6634c7f Merge "clang-format on vttreader.cc"
7566004 Merge "clang-format on vttdemux.cc"
9915b84 clang-format on mkvreader.[ch]pp
7437254 clang-format on mkvmuxertypes.hpp and webmids.hpp
0d5a98c clang-format on sample_muxer.cpp
e3485c9 clang-format on vttdemux.cc
46cc823 clang-format on dumpvtt.cc
5218bd2 clang-format on vttreader.cc
1a0130d clang-format on sample_muxer_metadata.(cc|h)
867f189 clang-format on sample.cpp
4c7bec5 clang-format on mkvwriter.[ch]pp
9ead078 clang-format on mkvmuxerutil.[ch]pp
fb6b6e6 clang-format on mkvmuxer.[ch]pp
ce77592 Update .clang-format to allow short functions in one line
0a24fe4 Merge "Add support for DateUTC and DefaultDuration in MKV Muxer."
11d5b66 Merge "Add .clang-format"
a1a3b14 Add .clang-format
0fcec38 Add support for DateUTC and DefaultDuration in MKV Muxer.

Change-Id: Ia0ed161ffc3d63c2eba8ed145707ffe543617976

Add idct_dequant_full_2x_neon.c
- idct_dequant_full_2x_neon

==== Summary of apply VP8 decode patch series ====
Benchmark on Samsung Chromebook, Cortex-A15, 1.7GHz, Dual core
Toolchain: linaro-1.13.1-4.8-2014.01
Compile argument: CROSS=arm-linux-gnueabihf- ../libvpx/configure
                     --target=armv7-linux-gcc --prefix=$HOME/out
                     --enable-shared --cpu=cortex-a7
Test argument: vpxdec --summary --noblit ./tears_of_steel_1080p.webm

NEON assembly   46.68 (fps)
Apply patch 06  46.65, -0.03
Apply patch 07  46.86, +0.21
Apply patch 08  46.58, -0.28
Apply patch 09  46.57, -0.01
Apply patch 10  46.51, -0.06
Apply patch 11  46.13, -0.38
Apply patch 12  45.42, -0.71
Apply patch 13  46.06, +0.64
Apply patch 14  45.19, -0.87
Apply patch 15  45.93, +0.74
Apply patch 16  45.48, -0.45
Apply patch 17  45.84, +0.36
Apply patch 18  45.91, +0.07  <= With all NEON intrinsics patches
                 Total -0.77 fps, 1.65% performance regression

Change-Id: I77bfc9eaccfb97b8d401e949ceff8795e26ca6b7
Signed-off-by: James Yu <james.yu@linaro.org>

Match x86_abi_support.asm configuration

Change-Id: Ic0d03a23961e6858cf5153389ec8afa0fae3307a

When ARNR filtering is disabled, by setting
arnr_max_frames=0, mode_skip_mask was being set to
-1 for the ARF frame resulting in no mode being
selected for the block.

The intent is to restrict the reference frame to the
previous ARF frame and the mode to one of ZEROMV,
NEARMV or NEARESTMV.

Change-Id: Ifc3920b153142cd01d422910c94d2f20ffb6f129

On balance Deb's  modified rate control for VBR seems
to be outperforming especially on some low motion YT
clips so I have switched this to be the default mode for
now.

Change-Id: I0713d430cad6425ac5c48fccdf332e12814ee44a

Change-Id: Ib56df7cd282dadbfd202de23f0c746a93b5ce63e

Change-Id: I0d50354111df79b74aafcd3bb7dc14df3c14733a

When used --show-program-output shows the output from the programs run
during testing.

Change-Id: I15a47c43d1fcf0243c8df1a75d0d2a584ae1f08f

Change-Id: Idccb530c814cb8a2fb9f7d0c11eaef25044efe5e

Change-Id: Id6ab59e505be28cd4eb9f1fe114feb47debe0539

Change-Id: I7cc6f441f414ca1b4d95dad3f789fff6faf8c3c4

Change-Id: I34ebc59980cf661ed658555e245bf0a93e5c3373

Corresponding C functions were removed in
I99695564a3aa9bc8c79ac0a551d257e2ff3ad3c3

Change-Id: I50a5575065a7a9e41904eb2161afd739def927db

Add a verbose logging function instead of checking
$VPX_TEST_VERBOSE_OUTPUT in multiple places.

Change-Id: I82618809f0964f696ed17ca4d99d8d7d252232f4

Don't update the stats if we have a corrupted frame.

Change-Id: I65a13adc50e0389b4201d3b671f0225195dfaff4
TODO: Test case that shows this problem.

Added in preparation for modifications to support high bitdepth
operations.

Change-Id: I1ad403ea8886cb84020ff06807ae25e2e4bff608

Used horizonal add instructions instead of adding
byte lanes.  The encoder performance improved by
~4% for the test clip used.

Change-Id: Iaddd10403fcffb5b3f53b1f591ab2fe0ff002c08