Roll Skia from 9e8f31e3020c to 486deb23bc2a (2 revisions) (flutter#38574)

https://skia.googlesource.com/skia.git/+log/9e8f31e3020c..486deb23bc2a

2022-12-30 johnstiles@google.com Make uniforms in SkSLTest more data-driven.
2022-12-30 johnstiles@google.com Remove unused and unassigned `testInput` uniform.

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 garyq@google.com,robertphillips@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': '9e8f31e3020c1eaa3ebdb5aa39bc756b5e2f40a0',
+  'skia_revision': '486deb23bc2a4d3d09c66fef52c2ad64d8b4f761',
 
   # WARNING: DO NOT EDIT canvaskit_cipd_instance MANUALLY
   # See `lib/web_ui/README.md` for how to roll CanvasKit to a new version.