Revert "Roll Dart SDK from a507a9057730 to f18aa4402c1a (3 revisions) (#39395)" (#39422)

This reverts commit ec45e72.

Author: zanderso

DEPS

@@ -48,7 +48,7 @@ vars = {
   # Dart is: https://github.com/dart-lang/sdk/blob/main/DEPS
   # You can use //tools/dart/create_updated_flutter_deps.py to produce
   # updated revision list of existing dependencies.
-  'dart_revision': 'f18aa4402c1a9148ab9b7dfe756083f8102336e0',
+  'dart_revision': 'a507a9057730514e2cf68e1ab405aa5afeec1eef',
 
   # 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

@@ -1,4 +1,4 @@
-Signature: 3c9613dc3c44f28a6c7140e074d4f1e8
+Signature: 5a7ee52dd5671337142fb4d694a028ef
 
 ====================================================================================================
 LIBRARY: angle