Roll src/third_party/libvpx/source/libvpx/ 181988d37..243029faf (45 commits).

$ git log 181988d37..243029faf --date=short --no-merges --format='%ad %ae %s'
2016-06-22 thakis win: Include <intrin.h> instead of manually declaring intrinsics.
2016-06-22 yaowu Prevent negative variance
2016-06-20 yaowu Fix ubsan warnings: vp9/encoder/vp9_mcomp.c
2016-06-15 huisu Add a hardware compatibility feature
2016-06-20 yaowu Make type conversion explicit
2016-06-19 johannkoenig Fix outdated reference to
2016-06-18 jzern realtime_test: remove decoded frame count check
2016-06-17 jingning Refactor optimize_b for speed performance
2016-06-17 jingning Port optimize_b speed-up from vp10
2016-06-17 yaowu Fix ubsan warning: vp9/encoder/vp9_encodeframe.c
2016-06-17 jingning Use 64-bit integer to store distortion in optimize_b
2016-06-17 johannkoenig Configuration: Use 'is_in' instead of echo | grep
2016-06-10 johannkoenig Parse codec options in order of occurrence.
2016-06-15 tomfinegan Disable neon for Xcode versions < v6.3.
2016-06-17 gezalore Fix warnings from gtest under GCC 5 or newer.
2016-06-15 tomfinegan Output frames in first pass for VPX_DL_REALTIME.
2016-06-17 yaowu Fix ubsan warnings: vp9/encoder/vp9_encoder.c
2016-06-16 johannkoenig Remove
2016-06-13 johannkoenig vp8_[cd]x_iface.c: Initialize structures to 0
2016-06-13 johannkoenig VP8_COMP: make frames_since_golden signed

Cr-Commit-Position: refs/heads/master@{#401411}
6 files changed