Roll Dart SDK from 33b6c95936e0 to a2c9cae4dcd8 (1 revision) (flutter#21027)

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': '33b6c95936e047b81d0a0ec356e81398f64ba52d',
+  'dart_revision': 'a2c9cae4dcd802dd2c2972b981a27ee7a58f659f',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py
@@ -226,7 +226,7 @@ deps = {
    Var('dart_git') + '/intl.git' + '@' + Var('dart_intl_tag'),
 
   'src/third_party/dart/third_party/pkg/json_rpc_2':
-   Var('dart_git') + '/json_rpc_2.git@995611cf006c927d51cc53cb28f1aa4356d5414f',
+   Var('dart_git') + '/json_rpc_2.git@8f189db8f0c299187a0e8fa959dba7e9b0254be5',
 
   'src/third_party/dart/third_party/pkg/linter':
    Var('dart_git') + '/linter.git' + '@' + Var('dart_linter_tag'),

ci/licenses_golden/licenses_third_party

@@ -1,4 +1,4 @@
-Signature: dcb76d0b2acce93dc9118883aff2c084
+Signature: cdd12c4e61799cb365d256582ce9a8c1
 
 UNUSED LICENSES: