Roll src/third_party/skia 50ea3c06b80f..2d35a1c87553 (6 commits) (flutter/engine#7693)

https://skia.googlesource.com/skia.git/%2Blog/50ea3c06b80f..2d35a1c87553

git log 50ea3c06b80f7322c64fd99926edcdd7ea398213..2d35a1c875539b744631a75a037f2b5d2e72c31f --date=short --no-merges --format=%ad %ae %s
2019-02-01 egdaniel@google.com Move texture release proc to GrSurface so that render targets can also have releases.
2019-02-04 recipe-roller@chromium.org Roll recipe dependencies (trivial).
2019-02-04 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/swiftshader 612345523a8d..049ff3873334 (1 commits)
2019-02-04 bungeman@google.com Extend GetAlphaTextureBounds workaround.
2019-02-04 bungeman@google.com Make HR* macros statements.
2019-02-04 robertphillips@google.com Rename GrContext::contextPriv to priv

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 (fmalita@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': '50ea3c06b80f7322c64fd99926edcdd7ea398213',
+  'skia_revision': '2d35a1c875539b744631a75a037f2b5d2e72c31f',
 
   # 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: 36c4a454b9ac0cbe7ed95735c8186d70
+Signature: 9c973b58e35bf1b511604299a4ac4ef9
 
 UNUSED LICENSES: