Roll Skia from 36f3c3fbec19 to c3a3d1e47699 (2 revisions) (flutter#175181)

https://skia.googlesource.com/skia.git/+log/36f3c3fbec19..c3a3d1e47699

2025-09-10 briansalomon@gmail.com rm unused tools/gpu/FenchSync.h file
2025-09-10 syoussefi@google.com [graphite][vulkan] Use
VK_EXT_host_image_copy

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 brettos@google.com,codefu@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://issues.skia.org/issues/new?component=1389291&template=1850622

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md

Author: engine-flutter-autoroll

DEPS

@@ -14,7 +14,7 @@ vars = {
   'flutter_git': 'https://flutter.googlesource.com',
   'skia_git': 'https://skia.googlesource.com',
   'llvm_git': 'https://llvm.googlesource.com',
-  'skia_revision': '36f3c3fbec192ca3f99c034297d03c2cb0d155fd',
+  'skia_revision': 'c3a3d1e47699338c7f02618a00772f7ebdf1b8e8',
 
   # WARNING: DO NOT EDIT canvaskit_cipd_instance MANUALLY
   # See `lib/web_ui/README.md` for how to roll CanvasKit to a new version.