Allow arity checks on dynamic function types

test/dart_codegen/expect/async/async_error.dart

Index: test/dart_codegen/expect/async/async_error.dart
diff --git a/test/dart_codegen/expect/async/async_error.dart b/test/dart_codegen/expect/async/async_error.dart
index 5b37f9ac2f2d8fd3e26820a3e3447b05f3315ff7..26b2f4e7d4c90c43d40be9e2ecbbf847bdc7d92c 100644
--- a/test/dart_codegen/expect/async/async_error.dart
+++ b/test/dart_codegen/expect/async/async_error.dart
@@ -12,7 +12,7 @@ part of dart.async;
     return zone.registerBinaryCallback(errorHandler);
     }
    else {
-    return zone.registerUnaryCallback(DEVC$RT.cast(errorHandler, Function, __t0, "CastGeneral", """line 20, column 39 of dart:async/async_error.dart: """, errorHandler is __t0, false));
+    return zone.registerUnaryCallback(DEVC$RT.cast(errorHandler, Function, __t0, "CastGeneral", """line 20, column 39 of dart:async/async_error.dart: """, errorHandler is __t0, true));
     }
   }
  class _UncaughtAsyncError extends AsyncError {_UncaughtAsyncError(error, StackTrace stackTrace) : super(error, _getBestStackTrace(error, stackTrace));