Roll Dart SDK from 9aca08d40398 to 4574906880c1 (1 revision) (flutter#46435)

https://dart.googlesource.com/sdk.git/+log/9aca08d40398..4574906880c1

2023-09-30 dart-internal-merge@dart-ci-internal.iam.gserviceaccount.com Version 3.2.0-218.0.dev

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/dart-sdk-flutter-engine
Please CC dart-vm-team@google.com,jacksongardner@google.com on the revert to ensure that a human
is aware of the problem.

To file a bug in Flutter Engine: 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

@@ -57,7 +57,7 @@ vars = {
   # Dart is: https://github.com/dart-lang/sdk/blob/main/DEPS
   # You can use //tools/dart/create_updated_flutter_deps.py to produce
   # updated revision list of existing dependencies.
-  'dart_revision': '9aca08d40398186ee4533e0d7b62b2a3ab6283ef',
+  'dart_revision': '4574906880c1aad311e8153ef612c94d27e1add1',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py

ci/licenses_golden/licenses_dart

@@ -1,4 +1,4 @@
-Signature: 8ea9728707a99334f879db79627b0dc2
+Signature: bb5b5af01a6378a3c134c7bbe6270f40
 
 ====================================================================================================
 LIBRARY: dart