Roll src/third_party/skia 51e15a69ce5b..4497ac179949 (1 commits) (flutter/engine#8893)

https://skia.googlesource.com/skia.git
/%2Blog/51e15a69ce5b..4497ac179949

git log 51e15a69ce5bef01ff0d0b5ae3d72c1b2ad3f799..4497ac17994900308f2630ca1613a3e24c6fd362 --date=short --no-merges --format=%ad %ae %s
2019-05-08 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/swiftshader b01f2559e017..d5ed0a31ce88 (10 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 (robertphillips@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': '51e15a69ce5bef01ff0d0b5ae3d72c1b2ad3f799',
+  'skia_revision': '4497ac17994900308f2630ca1613a3e24c6fd362',
 
   # When updating the Dart revision, ensure that all entries that are
   # dependencies of Dart are also updated to match the entries in the

engine/src/flutter/ci/licenses_golden/licenses_skia

@@ -1,4 +1,4 @@
-Signature: 33b4ed077689b7069d30e38bce3c7db7
+Signature: 12994088b98be341249859336fafa85e
 
 UNUSED LICENSES: