Roll src/third_party/skia e56cc054dbae..ab26643258ad (3 commits) (flutter#14273)

https://skia.googlesource.com/skia.git/+log/e56cc054dbae..ab26643258ad

git log e56cc054dbae..ab26643258ad --date=short --first-parent --format='%ad %ae %s'
2019-12-10 skia-autoroll@skia-public.iam.gserviceaccount.com Roll ../src 4e96c2bed379..ffcaa57570c0 (398 commits)
2019-12-10 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/angle2 27c89d2b5c56..f60da87424a4 (8 commits)
2019-12-10 recipe-mega-autoroller@chops-service-accounts.iam.gserviceaccount.com Roll recipe dependencies (trivial).

Created with:
  gclient setdep -r src/third_party/skia@ab26643258ad

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 djsollen@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: djsollen@google.com

Author: skia-flutter-autoroll

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': 'e56cc054dbaebdacf93716c761f45fda3a6d5817',
+  'skia_revision': 'ab26643258ad78cb100e9d9e5eaf8ad06d8c639d',
 
   # 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

@@ -1,4 +1,4 @@
-Signature: 0fb191ffcaf6126977f09ce49d0445df
+Signature: 0400e2940c1c54d6cda0e3950766318b
 
 UNUSED LICENSES: