Roll Dart SDK from 2d22e4ca26ef to d2628a71067d (3 revisions) (flutter#19231)

Author: skia-flutter-autoroll

DEPS

@@ -34,7 +34,7 @@ vars = {
   # Dart is: https://github.com/dart-lang/sdk/blob/master/DEPS.
   # You can use //tools/dart/create_updated_flutter_deps.py to produce
   # updated revision list of existing dependencies.
-  'dart_revision': '2d22e4ca26efad00d4ab61af08795c538d157a36',
+  'dart_revision': 'd2628a71067dd352774f4194b3db6748bfa5f1b2',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py