Roll Skia from b9671fd75308 to f6b4344d73cc (1 revision) (flutter#53530)

https://skia.googlesource.com/skia.git/+log/b9671fd75308..f6b4344d73cc

2024-06-24 bungeman@google.com Manual roll of skp

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,jsimmons@google.com,rmistry@google.com,scroggo@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: skia-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': 'b9671fd753089d548c580c1ce33d705a8b3db84e',
+  'skia_revision': 'f6b4344d73cced1d370c0c0ca4943f4cc1cd071e',
 
   # WARNING: DO NOT EDIT canvaskit_cipd_instance MANUALLY
   # See `lib/web_ui/README.md` for how to roll CanvasKit to a new version.