Roll src/third_party/dart 017b1c46f6d5..518f09726660 (2 commits) (#18252)

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': '017b1c46f6d568dec14bd24e5fdfc89238f77400',
+  'dart_revision': '518f097266606c35fd192617839d0dc8590a8671',
 
   # 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: aeb404ab90a5c8ca913282e3125c9e27
+Signature: c2f976c8fa33631338bd3aca4911a505
 
 UNUSED LICENSES: