Roll Skia from 476ee3fd54cc to 84630c3c18b2 (5 revisions) (flutter/engine#41316)

https://skia.googlesource.com/skia.git/+log/476ee3fd54cc..84630c3c18b2

2023-04-18 jmbetancourt@google.com [skottie] pass slot id to opacity callback
2023-04-18 robertphillips@google.com [graphite] Have ResourceCache call ProxyCache::freeUniquelyHeld
2023-04-18 skia-autoroll@skia-public.iam.gserviceaccount.com Roll vulkan-deps from 6a521002def5 to 9263fd4841e9 (1 revision)
2023-04-18 armansito@google.com [graphite] Declare UniformManager tests with DEF_GRAPHITE_TEST
2023-04-18 briansalomon@gmail.com [bazel] git_repos_from_deps takes optional workspace parameter

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,chinmaygarde@google.com,jmbetancourt@google.com,rmistry@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': '476ee3fd54ccb6955904f9dc3ce72a3ed05bf1a8',
+  'skia_revision': '84630c3c18b209aa1e8111d67295e1451f1a7790',
 
   # WARNING: DO NOT EDIT canvaskit_cipd_instance MANUALLY
   # See `lib/web_ui/README.md` for how to roll CanvasKit to a new version.

engine/src/flutter/ci/licenses_golden/licenses_skia

@@ -1,4 +1,4 @@
-Signature: 42a1373c7fe9f4eaa27dee32fb426d14
+Signature: a1dcf7886bcb498c56caceaf45f7cb93
 
 ====================================================================================================
 LIBRARY: etc1