Roll Dart SDK from b98a1eec5eb5 to 6ecae204598d (1 revision) (#25874)

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': 'b98a1eec5eb5727f6d211b08daf5c2b5fe27d072',
+  'dart_revision': '6ecae204598d0c3767786b96f6e759523b0a7d3a',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py

ci/licenses_golden/licenses_third_party

-Signature: 718f8841031abaf0593c0a9587ba2858
+Signature: 0cd97bc3f34ac40583de63d2f282fdba
 
 UNUSED LICENSES: