Roll src/third_party/skia ac29f1342fd2..a2d7225c0fc1 (5 commits) (#14677)

https://skia.googlesource.com/skia.git/+log/ac29f1342fd2..a2d7225c0fc1

git log ac29f1342fd2..a2d7225c0fc1 --date=short --first-parent --format='%ad %ae %s'
2019-12-23 herb@google.com Internalize vertexStride calculation to SubRun
2019-12-23 herb@google.com Remove unneeded refStrike() from SubRun
2019-12-23 skia-autoroll@skia-public.iam.gserviceaccount.com Roll ../src 1c1af9fcab8f..bd5c3742938c (425 commits)
2019-12-23 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/angle2 fe2ed33a56dd..07d3bcf1c443 (10 commits)
2019-12-23 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/swiftshader 6d29348ddb7e..6e3a387c0159 (4 commits)

Created with:
  gclient setdep -r src/third_party/skia@a2d7225c0fc1

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/skia-flutter-autoroll
Please CC fmalita@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

Bug: None
Tbr: fmalita@google.com

DEPS

@@ -26,7 +26,7 @@ vars = {
   'skia_git': 'https://skia.googlesource.com',
   # OCMock is for testing only so there is no google clone
   'ocmock_git': 'https://github.com/erikdoe/ocmock.git',
-  'skia_revision': 'ac29f1342fd2dbf4928b204680edffbe20ae617c',
+  'skia_revision': 'a2d7225c0fc1a85e861df30f7f97638e4eea6937',
 
   # When updating the Dart revision, ensure that all entries that are
   # dependencies of Dart are also updated to match the entries in the

ci/licenses_golden/licenses_skia

-Signature: c38e352bcab109a04a45413db2329d6a
+Signature: 036c80409280fe7f6497444167f82402
 
 UNUSED LICENSES: