Roll Skia from a8b7ce3b6391 to 38d9c68d35c6 (2 revisions) (flutter/engine#38492)

https://skia.googlesource.com/skia.git/+log/a8b7ce3b6391..38d9c68d35c6

2022-12-24 skia-autoroll@skia-public.iam.gserviceaccount.com Roll vulkan-deps from 32a3297e82b4 to 259eec71c7c6 (2 revisions)
2022-12-23 skia-autoroll@skia-public.iam.gserviceaccount.com Roll vulkan-deps from 70e74a2f82ab to 32a3297e82b4 (1 revision)

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 chinmaygarde@google.com,kjlubick@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': 'a8b7ce3b63914737f4d75e53126ac71912e59dfc',
+  'skia_revision': '38d9c68d35c606664c0277f07985f4968da1fbe3',
 
   # WARNING: DO NOT EDIT canvaskit_cipd_instance MANUALLY
   # See `lib/web_ui/README.md` for how to roll CanvasKit to a new version.