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