Roll src/third_party/dart 2497606fed87..c6db98667aa6 (4 commits) (#18289)

diff --git a/DEPS b/DEPS
index f0ee596..ee49c67 100644
--- a/DEPS
+++ b/DEPS
@@ -34,7 +34,7 @@
   # 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': '2497606fed8728b29a3491e6945e43f47efe113f',
+  'dart_revision': 'c6db98667aa67231d10d81c65b1640d4ef27a5ce',
 
   # WARNING: DO NOT EDIT MANUALLY
   # The lines between blank lines above and below are generated by a script. See create_updated_flutter_deps.py
diff --git a/ci/licenses_golden/licenses_third_party b/ci/licenses_golden/licenses_third_party
index 2cc0a9d..863d56e 100644
--- a/ci/licenses_golden/licenses_third_party
+++ b/ci/licenses_golden/licenses_third_party
@@ -1,4 +1,4 @@
-Signature: 2dbb661928dd1e475a50e75fda85ab7e
+Signature: 276baedd256f7d4fdf83e8afc14f8112
 
 UNUSED LICENSES: