Roll src/third_party/skia 8676929c0a13..893403fb3896 (6 commits) (#9421)

https://skia.googlesource.com/skia.git
/%2Blog/8676929c0a13..893403fb3896

git log 8676929c0a13560d874e6c274df64f89b0769045..893403fb389695fc3517aae7f74e5c895f716e82 --date=short --no-merges --format=%ad %ae %s
2019-06-21 mtklein@google.com clarify can-we-call-JIT logic
2019-06-21 mtklein@google.com rearrange who mprotects
2019-06-20 robertphillips@google.com Fix up wacky_yuv_formats GM
2019-06-20 herb@google.com Start using new APIs for bounds and glyph lookup
2019-06-21 nifong@google.com Reland "Deserialize MultiPictureDocument based SKP files (with image sharing proc) in wasm debugger."
2019-06-21 jvanverth@google.com Fix Mac viewer on command line launch.

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 (bsalomon@google.com), and stop
the roller if necessary.

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': '8676929c0a13560d874e6c274df64f89b0769045',
+  'skia_revision': '893403fb389695fc3517aae7f74e5c895f716e82',
 
   # 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: 840ca5e25666b9cee522981c966b4e44
+Signature: 17db75aebf1d4946c4ee3afccb724c51
 
 UNUSED LICENSES: