Roll Dart SDK from 50b96abe9f6f to 4cc2e637a315 (1 revision)

https://dart.googlesource.com/sdk.git/+log/50b96abe9f6f..4cc2e637a315

2023-04-20 dart-internal-merge@dart-ci-internal.iam.gserviceaccount.com Version 3.1.0-27.0.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 aam@google.com,chinmaygarde@google.com,dart-vm-team@google.com,rmistry@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

@@ -47,7 +47,7 @@ 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': '50b96abe9f6f132110a4fbe4d49590b8f4f31651',
+  'dart_revision': '4cc2e637a3153ba6c13bbcfa89966bfcabce3002',
 
   # 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_third_party

@@ -1,4 +1,4 @@
-Signature: 1377370be3708898d4f3d92157ffc1e6
+Signature: eb6124d7bb7d781a6f74d6d90359097b
 
 ====================================================================================================
 LIBRARY: angle