Roll Dart SDK from 7128b5b5142c to 8fdbf58b58bd (1 revision) (#184906)

https://dart.googlesource.com/sdk.git/+log/7128b5b5142c..8fdbf58b58bd

2026-04-11 dart-internal-merge@dart-ci-internal.iam.gserviceaccount.com
Version 3.13.0-9.0.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
Please CC dart-vm-team@google.com,jimgraham@google.com on the revert to
ensure that a human
is aware of the problem.

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

DEPS

diff --git a/DEPS b/DEPS
index c7159e9..b234083 100644
--- a/DEPS
+++ b/DEPS
@@ -59,7 +59,7 @@
   # updated revision list of existing dependencies. You will need to
   # gclient sync before and after update deps to ensure all deps are updated.
   # updated revision list of existing dependencies.
-  'dart_revision': '7128b5b5142c44b35c140405bff198f6acaefd50',
+  'dart_revision': '8fdbf58b58bdcb268c3ac59d2c138c78753245b2',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py