Roll Dart SDK from 366b33929a85 to 21060985e0b6 (1 revision) (#25035)

DEPS

@@ -35,7 +35,7 @@ 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': '366b33929a85c6cf2bb7a32d498857691a9b1405',
+  'dart_revision': '21060985e0b60d77bf38c0d70f06ae7d2929adbb',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py
@@ -43,7 +43,7 @@ vars = {
   'dart_boringssl_rev': '1607f54fed72c6589d560254626909a64124f091',
   'dart_clock_rev': 'a494269254ba978e7ef8f192c5f7fec3fc05b9d3',
   'dart_collection_rev': '9967dcd3d7645db6de48d5abfab3018bb0c84236',
-  'dart_dart_style_tag': 'a1d65dd9c4b83c9702ba409465879b94caeb04ea',
+  'dart_dart_style_tag': '2cf810073e0cc7e7ea05d3de51830e6fa6d62924',
   'dart_http_throttle_tag': '1.0.2',
   'dart_intl_tag': '0.17.0-nullsafety',
   'dart_linter_tag': '1.0.0',

ci/licenses_golden/licenses_third_party

-Signature: b2f0005f0caa77b96d26fef41999b361
+Signature: 529de0485a6149f305b9964e55e09e3f
 
 UNUSED LICENSES: