Roll Dart SDK from 20f429feabbe to 2373719d3d0c (1 revision) (#181164)

https://dart.googlesource.com/sdk.git/+log/20f429feabbe..2373719d3d0c

2026-01-19 dart-internal-merge@dart-ci-internal.iam.gserviceaccount.com
Version 3.12.0-45.0.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 1a00316..8bf5bed 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': '20f429feabbef5e93c737d344010a79b8dd95414',
+  'dart_revision': '2373719d3d0caf3f2ac8072ad5ac7dd32aa5ee68',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py