Roll src/third_party/skia/ a273c0f66..02cb4d469 (11 commits).

https://chromium.googlesource.com/skia.git/+log/a273c0f6676b..02cb4d469a2a

$ git log a273c0f66..02cb4d469 --date=short --no-merges --format='%ad %ae %s'
2016-01-25 msarett Disable RAW test on Chrome OS, Windows
2016-01-25 msarett Fix leak of SkImageGenerator
2016-01-25 joshualitt Build and link microhttpd from gyp
2016-01-25 benjaminwagner Remove RAW Codec from Google3 build.
2016-01-25 mtklein spin off some safe parts from AVX2 CL
2016-01-25 msarett Revert of AVX 2 SrcOver blits: color32, blitmask. (patchset #24 id:450001 of https://codereview.chromium.org/1532613002/ )
2016-01-25 robertphillips Add GM for SkPixelXorXfermode
2016-01-25 mtklein AVX 2 SrcOver blits: color32, blitmask.
2016-01-25 yujieqin Add RAW decoding into Skia.
2016-01-25 msarett Do not test images with alpha to 565
2016-01-25 cjacek Fixed compilation on mingw.

CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
TBR=msarett@google.com

Review URL: https://codereview.chromium.org/1634813002

Cr-Commit-Position: refs/heads/master@{#371308}

DEPS

@@ -39,7 +39,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling Skia
   # and whatever else without interference from each other.
-  'skia_revision': 'a273c0f6676b261ef82bc43b0dcc53282f2bdf8c',
+  'skia_revision': '02cb4d469a2abde1119947eccb1de4aec37557a7',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.