Roll src/third_party/skia 2b3b17304bf8..b4f854080375 (2 commits)

https://skia.googlesource.com/skia.git/+log/2b3b17304bf8..b4f854080375

git log 2b3b17304bf8..b4f854080375 --date=short --no-merges --format='%ad %ae %s'
2019-11-21 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/angle2 99bd10b70422..b8e748be6b94 (17 commits)
2019-11-21 skia-autoroll@skia-public.iam.gserviceaccount.com Roll ../src 0db96f99..137e8082 (617 commits)

Created with:
  gclient setdep -r src/third_party/skia@b4f854080375

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/skia-autoroll
Please CC robertphillips@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

CQ_INCLUDE_TRYBOTS=luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux-blink-rel;luci.chromium.try:linux-chromeos-compile-dbg;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel
TBR=robertphillips@google.com

Bug: chromium:None,chromium:None
Change-Id: I1f6326e0d068b75e187778ccc2dfdf392e84631c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1928223Reviewed-by: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Commit-Queue: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#717544}

DEPS

@@ -172,7 +172,7 @@ 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': '2b3b17304bf8c6532d7177e6c74d0a2403e52924',
+  'skia_revision': 'b4f854080375637c3e3bc67ee157ce1190eae3f7',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.