anchor.diff:      _inputSubscription?.cancel();
   
       for (final pending in _pendingRequests.values) {
  -      pending.completeError(const ConnectionClosedException());
  +      pending.completeWithError(const ConnectionClosedException());
       }
       _pendingRequests.clear();
     }
  
positive.code:   }
  }
  
  /// Exception thrown when there are outstanding pending requests at the time the
  /// isolate connection was cancelled.
  class ConnectionClosedException implements Exception {
  
negative.code:   // (one per remote). Each of them has an independent _currentRequestId field
    int _currentRequestId = 0;
    final Completer<void> _closeCompleter = Completer();
    final Map<int, _PendingRequest> _pendingRequests = {};
    final StreamController<Request> _incomingRequests =
        StreamController(sync: true);
  
    /// Starts a drift communication channel over a raw [StreamChannel].
    DriftCommunication(this._channel,
  