Roll Skia from bfc7c3a83dc0 to 6f6793b298ff (4 revisions) (flutter#38007)

https://skia.googlesource.com/skia.git/+log/bfc7c3a83dc0..6f6793b298ff

2022-12-01 cmumford@google.com bazel: Presubmit for out-of-date build file.
2022-12-01 cmumford@google.com Bazel: Remove exporter_tool CheckCurrent method.
2022-12-01 johnstiles@google.com Fix LoadStoreConditionMask test in RP scalar mode.
2022-12-01 kjlubick@google.com [includes] Fix includes of SkFixed.h

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 bungeman@google.com,zra@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

Author: skia-flutter-autoroll

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': 'bfc7c3a83dc0862d6ffc354d6d61db1d077073a0',
+  'skia_revision': '6f6793b298ff501a9582a5ff03d2b3657e2f47d0',
 
   # WARNING: DO NOT EDIT canvaskit_cipd_instance MANUALLY
   # See `lib/web_ui/README.md` for how to roll CanvasKit to a new version.

ci/licenses_golden/licenses_skia

@@ -1,4 +1,4 @@
-Signature: 0b4cad60a21909dae4b195f3166e87be
+Signature: 172f94b0c27e4c94ba1b2a8d402ffb83
 
 UNUSED LICENSES: