Roll Dart SDK from 302893b93170 to 58a209093c38 (1 revision) (flutter#20552)

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': '302893b931709e03e7e1b811ac07b7edbc994b0b',
+  'dart_revision': '58a209093c3884083dc7ae69f23395546d2d2f59',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py