Roll Skia from 9fa8ebdfdbb8 to 68b80f663be6 (1 revision) (flutter/engine#44511)

https://skia.googlesource.com/skia.git/+log/9fa8ebdfdbb8..68b80f663be6

2023-08-08 nicolettep@google.com Add some nullchecks to GrTriangulator

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 brianosman@google.com,chinmaygarde@google.com,kjlubick@google.com,rmistry@google.com on the revert to ensure that a human
is aware of the problem.

To file a bug in Skia: https://bugs.chromium.org/p/skia/issues/entry
To file a bug in Flutter: https://github.com/flutter/flutter/issues/new/choose

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/+doc/main/autoroll/README.md

DEPS

@@ -18,7 +18,7 @@ vars = {
   'llvm_git': 'https://llvm.googlesource.com',
   # OCMock is for testing only so there is no google clone
   'ocmock_git': 'https://github.com/erikdoe/ocmock.git',
-  'skia_revision': '9fa8ebdfdbb8fa2b122f452be7eef113e378f931',
+  'skia_revision': '68b80f663be6bdb87e24d732d1cef5619b02fdd2',
 
   # WARNING: DO NOT EDIT canvaskit_cipd_instance MANUALLY
   # See `lib/web_ui/README.md` for how to roll CanvasKit to a new version.

engine/src/flutter/ci/licenses_golden/licenses_skia

@@ -1,4 +1,4 @@
-Signature: 92826d829c093192dde73478f4b6373b
+Signature: 81a2fe3a3b65f75195d276341feda77d
 
 ====================================================================================================
 LIBRARY: etc1