fix rpc exception for real (#38575)

packages/flutter_tools/lib/src/vmservice.dart

diff --git a/packages/flutter_tools/lib/src/vmservice.dart b/packages/flutter_tools/lib/src/vmservice.dart
index 05d37e8..a3de239 100644
--- a/packages/flutter_tools/lib/src/vmservice.dart
+++ b/packages/flutter_tools/lib/src/vmservice.dart
@@ -13,7 +13,6 @@
 import 'package:web_socket_channel/io.dart';
 import 'package:web_socket_channel/web_socket_channel.dart';
 
-import 'base/async_guard.dart';
 import 'base/common.dart';
 import 'base/context.dart';
 import 'base/file_system.dart';
@@ -359,7 +358,7 @@
   Future<void> _streamListen(String streamId) async {
     if (!_listeningFor.contains(streamId)) {
       _listeningFor.add(streamId);
-      await asyncGuard(() => _sendRequest('streamListen', <String, dynamic>{'streamId': streamId}));
+      await _sendRequest('streamListen', <String, dynamic>{'streamId': streamId});
     }
   }