Roll Dart SDK from fcd1c5b61ae8 to a3815b659047 (32 revisions) (#19933)

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': 'fcd1c5b61ae8b96e1cf639c9a419c85c4c4b3100',
+  'dart_revision': 'a3815b659047cfc6b63d41d180aa1ca1b781ee68',
 
   # 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: 719071d579b709defc2b0502e2fec5cc
+Signature: 466d6015ad82d4de20505a9f66fde95d
 
 UNUSED LICENSES:
 
@@ -8302,8 +8302,8 @@ FILE: ../../../third_party/dart/benchmarks/TypedDataDuplicate/dart/TypedDataDupl
 FILE: ../../../third_party/dart/benchmarks/TypedDataDuplicate/dart2/TypedDataDuplicate.dart
 FILE: ../../../third_party/dart/benchmarks/Utf8Decode/dart/Utf8Decode.dart
 FILE: ../../../third_party/dart/benchmarks/Utf8Decode/dart2/Utf8Decode.dart
-FILE: ../../../third_party/dart/runtime/bin/dartdev_utils.cc
-FILE: ../../../third_party/dart/runtime/bin/dartdev_utils.h
+FILE: ../../../third_party/dart/runtime/bin/dartdev_isolate.cc
+FILE: ../../../third_party/dart/runtime/bin/dartdev_isolate.h
 FILE: ../../../third_party/dart/runtime/bin/exe_utils.cc
 FILE: ../../../third_party/dart/runtime/bin/exe_utils.h
 FILE: ../../../third_party/dart/runtime/bin/platform_macos.h