Use HasToJson when set Reponse/Notification parameters.

pkg/analysis_server/lib/src/search/search_domain.dart

Index: pkg/analysis_server/lib/src/search/search_domain.dart
diff --git a/pkg/analysis_server/lib/src/search/search_domain.dart b/pkg/analysis_server/lib/src/search/search_domain.dart
index f7bab4130e627939bf5037a5e57a07220c10c17a..076ba42fdc275473ecc4d7a6228d6623733d0794 100644
--- a/pkg/analysis_server/lib/src/search/search_domain.dart
+++ b/pkg/analysis_server/lib/src/search/search_domain.dart
@@ -114,9 +114,7 @@ class SearchDomainHandler implements RequestHandler {
     Notification notification = new Notification(SEARCH_RESULTS);
     notification.setParameter(ID, searchId);
     notification.setParameter(LAST, isLast);
-    notification.setParameter(
-        RESULTS,
-        results.map(SearchResult.asJson).toList());
+    notification.setParameter(RESULTS, results);
     server.sendNotification(notification);
   }
 }