Roll Dart SDK from 2a2b8bc0b434 to 046c78d307d7 (1 revision)

https://dart.googlesource.com/sdk.git/+log/2a2b8bc0b434..046c78d307d7

2023-02-27 dart-internal-merge@dart-ci-internal.iam.gserviceaccount.com Version 3.0.0-276.0.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

@@ -48,7 +48,7 @@ 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': '2a2b8bc0b434db6d5e890b7ebc865e17d5d889c7',
+  'dart_revision': '046c78d307d71a4d60138bedee94256967f5056c',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py