Roll src/third_party/skia e2a903e18b59..6344cbd1df76 (3 commits) (#12357)

https://skia.googlesource.com/skia.git/+log/e2a903e18b59..6344cbd1df76

git log e2a903e18b59..6344cbd1df76 --date=short --no-merges --format='%ad %ae %s'
2019-09-19 skia-autoroll@skia-public.iam.gserviceaccount.com Roll ../src b1c1d2844bd1..b8149cbe28ad (423 commits)
2019-09-19 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/swiftshader 61a2765940a7..e9b6f28fdd71 (3 commits)
2019-09-19 mtklein@google.com fold srcover coverage with SkVMBlitter

Created with:
  gclient setdep -r src/third_party/skia@6344cbd1df76

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 brianosman@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=brianosman@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': 'e2a903e18b5963379bff86ff505a840cf1b52352',
+  'skia_revision': '6344cbd1df7634b4d583fd6a2878428ec331c026',
 
   # 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: ac00123f52d7702d384f87cd4a89add5
+Signature: 91097f982b4ec09ec3cf41fe74e4b315
 
 UNUSED LICENSES: