Roll Dart SDK from afc908f to 5bf47cb (1 revision) (#33745)

Author: skia-flutter-autoroll

DEPS

@@ -45,7 +45,7 @@ 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': 'afc908f0a5459d89d03017d59b21c1ab97b31554',
+  'dart_revision': '5bf47cbf2df239d246baf00bf6e52b71437fe47c',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py