anchor.diff:        if (completer != null) {
           try {
             await service.streamCancel(EventStreams.kDebug);
  -        } finally {
  +        } catch (_) {/* swallow exception */} finally {
             subscription.cancel();
             completer?.complete();
             completer = null;
  
positive.code:     if (event.kind == EventKind.kResume) {
        try {
          await service.streamCancel(EventStreams.kDebug);
        } finally {
          subscription.cancel();
          completer.complete();
        }
  
negative.code:     if (completer != null) {
        try {
          await service.streamCancel(EventStreams.kDebug);
        } catch (_) {/* swallow exception */} finally {
          subscription.cancel();
          completer?.complete();
        }
  