pull the latest from libwebp.

Original source:
 http://git.chromium.org/webm/libwebp.git
 100644 blob 264210ba2807e4da47eb5d18c04cf869d89b9784 src/utils/thread.c

commit 46fd44c1042c9903b2f1ab87e9f200a13c7e702d
Author: James Zern <jzern@google.com>
Date:   Tue Jul 8 19:53:28 2014 -0700

    thread: remove harmless race on status_ in End()

    if a thread was still doing work when End() was called there'd be a race
    on worker->status_. in these cases, however, the specific value is
    meaningless as it would be >= OK and the thread would have been shut
    down properly, but we'll check 'impl_' instead to avoid any potential
    TSan/DRD reports.

    Change-Id: Ib93cbc226a099f07761f7bad765549dffb8054b1

Change-Id: Ib0ef25737b3c6d017fa74822e21ed58508230b91

* changes:
  cpu_speed_test: cosmetics
  aq_segment_test: cosmetics

This commit enables a new quantization process for 32x32 2D-DCT
transform coefficient blocks. It improves the compression
performance of speed 5 by 1.4%. The overall compression gains of
speed 5 due to the new quantization scheme is 4.7%. It also includes
the SSSE3 implementation of the 32x32 quantization process.

Change-Id: I0855b124fd6462418683f783f5bcb44255c9993b

This patch fixes bug 633:
https://code.google.com/p/webm/issues/detail?id=633

The first decoded frame does not have to be a keyframe,
it could be an inter-frame that is coded intra-only.

This patch fixes the handling of intra-only frames.

A test vector has also been added that encodes 3
intra-only frames at the start of the clip. The
test vector was generated using the code in the
following patch:
https://gerrit.chromium.org/gerrit/#/c/70680/

Change-Id: Ib40b1dbf91aae2bc047e23c626eaef09d1860147

In the previous version, only certain buffers in the macroblockd were saved and
the restored. In this version, all of the buffers are saved and restored. The
code was then rolled into a loop for readability.

Also contains a tiny fix for when the -DOUTPUT_YUV_DENOISED flag is used.

Change-Id: Id925ef8b3fa122ae88acfa1d9a1e4df45df83518

vp8/encoder/x86/denoising_sse2.c:35:10: error: taking the absolute value
of unsigned type 'unsigned int' has no effect [-Werror,-Wabsolute-value]

Change-Id: I749ba8e6f55dbd9b822bfd4260a8397554f5e524

This makes it possible to use --rt --cpu-used=8.

Change-Id: I8b5bc4449b6e05d24d25145e35b4793501268c59

Change-Id: I7ec4e0e05487fe80d93e31e0f6a21f326b5c7276

Prepare for frame parallel decoding, the reference count buffers
need to be protected by mutex. Move vp9_thread.* to common
folder so that those buffers could use cross-platform mutex
from vp9_thread.*.

Change-Id: I541277cf15eefed6641555944f67f4a0bcdc8154

This commit further simplifies the SSSE3 implementation of the fast
path quantization process.

Change-Id: I5be3286ec0f1bd81d1cf5be3168fece6384fb9ca

Change-Id: Id6eedc502c86433df1456dd994aee6bc9a1359a2

* Replace max_step_search_steps with constant MAX_MVSEARCH_STEPS
* Fold (reduce_first_step_size + speed > 5) into reduce_first_step_size
  replacing uses of reduce_first_step_size that don't add the speed
  check with zero.

Change-Id: Iae46395dbf3eaca138bf4d18b838a9e364b5a198

The y4m extension used is the same as the one used in ffmpeg/x264.
The patch is adapted from the highbitdepth branch.

Also adds unit tests for y4m header parsing and md5 check
of the raw frame data, as well as y4m writing.

[build fix for Mac/VS by not using tuples with strings]

Change-Id: I40897ee37d289e4b6cea6fedc67047d692b8cb46

Merge "Reverting "Adds support for reading and writing 10/12-bit y4m" for now because of Mac Build Failure."

Reverting "Adds support for reading and writing 10/12-bit y4m" for now because of Mac Build Failure.

This reverts commit 82dc1332

Change-Id: I824bf42bf47c7df6985c79e451d6af913030d374

Change-Id: I39a37335ba5b3a969d328afb1f425ddb2cf7ddda

vp9_rdopt is for making rd optimal mode decisions. vp9_rd is for all
other rd related routines. Anything used outside of making an rd optimal
decision belongs in rd.

Change-Id: I772a3073f7588bdf139f551fb9810b6864d8e64b

Change-Id: I262ecac02d376de83097bb40f744f5584e987603

Moved the threshold adjustment before reference flag checking,
which could set the threshold to INT_MAX for disabled reference
frame, and cause overflow if the adjustment is done after that.

Change-Id: I85e94f8726d5e3ae93f65965aa978721dddc9957