Roll Skia from 4b16117e94b2 to a9db1213b179 (1 revision) (#49487)

https://skia.googlesource.com/skia.git/+log/4b16117e94b2..a9db1213b179

2023-12-21 johnstiles@google.com Fix IWYU inclusion of <atomic> when TRACE_EVENT is used.

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,egdaniel@google.com,rmistry@google.com,zra@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
diff --git a/DEPS b/DEPS
index 8eca110..0e3b0da 100644
--- a/DEPS
+++ b/DEPS
@@ -18,7 +18,7 @@
   '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': '4b16117e94b28e6a68d34f48db3a2beb5910628b',
+  'skia_revision': 'a9db1213b17966d0344957ba1d3834b420b2a329',
 
   # WARNING: DO NOT EDIT canvaskit_cipd_instance MANUALLY
   # See `lib/web_ui/README.md` for how to roll CanvasKit to a new version.
diff --git a/ci/licenses_golden/licenses_skia b/ci/licenses_golden/licenses_skia
index 8b97d0d..b61ca44 100644
--- a/ci/licenses_golden/licenses_skia
+++ b/ci/licenses_golden/licenses_skia
@@ -1,4 +1,4 @@
-Signature: 675feb91b4030c79a0eb24fbfa530845
+Signature: fb38b3d8e20c00a354d4e00a9c0c75ba
 
 ====================================================================================================
 LIBRARY: etc1
diff --git a/sky/packages/sky_engine/LICENSE b/sky/packages/sky_engine/LICENSE
index 9296811..89f11da 100644
--- a/sky/packages/sky_engine/LICENSE
+++ b/sky/packages/sky_engine/LICENSE
@@ -31145,7 +31145,7 @@
   This Source Code Form is "Incompatible With Secondary Licenses", as
   defined by the Mozilla Public License, v. 2.0.
 
-You may obtain a copy of this library's Source Code Form from: https://dart.googlesource.com/sdk/+/54ae1942813919819cf12265ca7eaf86e65d5a7f
+You may obtain a copy of this library's Source Code Form from: https://dart.googlesource.com/sdk/+/c5a75ac9057c2985b10bfa393c0a599049eac517
 /third_party/fallback_root_certificates/
 
 --------------------------------------------------------------------------------