Roll src/third_party/skia c88a3bc3f561..a7e557f3e353 (6 commits) (#15957)

https://skia.googlesource.com/skia.git/+log/c88a3bc3f561..a7e557f3e353

git log c88a3bc3f561..a7e557f3e353 --date=short --first-parent --format='%ad %ae %s'
2020-01-24 michaelludwig@google.com Reland "Increase precision of some quad AA calculations"
2020-01-24 recipe-mega-autoroller@chops-service-accounts.iam.gserviceaccount.com Roll recipe dependencies (trivial).
2020-01-23 reed@google.com remove legacy SkMScalar code
2020-01-23 mtklein@google.com use longer-lived alloc in CacheKey()
2020-01-23 mtklein@google.com force skvm interpreter in ASAN builds, add bots
2020-01-23 brianosman@google.com Use PipelineStageArgs throughout GrSkSLFP and PipelineStageCodeGenerator

Created with:
  gclient setdep -r src/third_party/skia@a7e557f3e353

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 benjaminwagner@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: benjaminwagner@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': 'c88a3bc3f56114100b941ca8ed8cc66092ebdd30',
+  'skia_revision': 'a7e557f3e353b665b52ecbcc2ef0f665811c92a1',
 
   # 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: 0b5740b0ff2a547fb39975b289e8c290
+Signature: 73daf088a395f4960bcf3302fabdf784
 
 UNUSED LICENSES:
 
@@ -1061,6 +1061,8 @@ FILE: ../../../third_party/skia/infra/bots/recipe_modules/build/examples/full.ex
 FILE: ../../../third_party/skia/infra/bots/recipe_modules/build/examples/full.expected/Build-Debian9-Clang-x86_64-Debug-OpenCL.json
 FILE: ../../../third_party/skia/infra/bots/recipe_modules/build/examples/full.expected/Build-Debian9-Clang-x86_64-Debug-SK_CPU_LIMIT_SSE41.json
 FILE: ../../../third_party/skia/infra/bots/recipe_modules/build/examples/full.expected/Build-Debian9-Clang-x86_64-Debug-SafeStack.json
+FILE: ../../../third_party/skia/infra/bots/recipe_modules/build/examples/full.expected/Build-Debian9-Clang-x86_64-Debug-SkVM.json
+FILE: ../../../third_party/skia/infra/bots/recipe_modules/build/examples/full.expected/Build-Debian9-Clang-x86_64-Debug-SkVM_ASAN.json
 FILE: ../../../third_party/skia/infra/bots/recipe_modules/build/examples/full.expected/Build-Debian9-Clang-x86_64-Debug-SwiftShader_MSAN.json
 FILE: ../../../third_party/skia/infra/bots/recipe_modules/build/examples/full.expected/Build-Debian9-Clang-x86_64-Debug-Tidy.json
 FILE: ../../../third_party/skia/infra/bots/recipe_modules/build/examples/full.expected/Build-Debian9-Clang-x86_64-Debug-Wuffs.json