Roll src/third_party/skia 3b60397fd35d..f74fff660084 (3 commits) (#8556)

https://skia.googlesource.com/skia.git/%2Blog/3b60397fd35d..f74fff660084

git log 3b60397fd35df09823b0c64fbf00ffc99ffe8c8c..f74fff66008417b661e3410f81a903e2f912480c --date=short --no-merges --format=%ad %ae %s
2019-04-12 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/angle2 e6b23e45b380..cfc73cc1af5e (5 commits)
2019-04-12 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/swiftshader 3954a0bafb8a..13f230772370 (11 commits)
2019-04-12 skia-autoroll@skia-public.iam.gserviceaccount.com Roll ../src f8764798ff0e..6506f553b36c (417 commits)

The AutoRoll server is located here: https://autoroll.skia.org/r/skia-flutter-autoroll

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

If the roll is causing failures, please contact the current sheriff (egdaniel@google.com), and stop
the roller if necessary.

DEPS

@@ -23,7 +23,7 @@ vars = {
   'fuchsia_git': 'https://fuchsia.googlesource.com',
   'github_git': 'https://github.com',
   'skia_git': 'https://skia.googlesource.com',
-  'skia_revision': '3b60397fd35df09823b0c64fbf00ffc99ffe8c8c',
+  'skia_revision': 'f74fff66008417b661e3410f81a903e2f912480c',
 
   # 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: 14c51d7f77a6feb3f3c406f5f1f0bc84
+Signature: c40861a2d729af36055a8b36c8e12c1e
 
 UNUSED LICENSES: