Add extra information for ReadingList ContentSuggestion

components/ntp_snippets/content_suggestion.cc

Index: components/ntp_snippets/content_suggestion.cc
diff --git a/components/ntp_snippets/content_suggestion.cc b/components/ntp_snippets/content_suggestion.cc
index e5cac6187ed26c3629246355769beb150a8d38e3..3341aad37d5534dfbce98e14fd1ba48ea6abe503 100644
--- a/components/ntp_snippets/content_suggestion.cc
+++ b/components/ntp_snippets/content_suggestion.cc
@@ -55,6 +55,12 @@ void ContentSuggestion::set_recent_tab_suggestion_extra(
   recent_tab_suggestion_extra_ = std::move(recent_tab_suggestion_extra);
 }
 
+void ContentSuggestion::set_reading_list_suggestion_extra(
+    std::unique_ptr<ReadingListSuggestionExtra> reading_list_suggestion_extra) {
+  DCHECK(id_.category().IsKnownCategory(KnownCategories::READING_LIST));
+  reading_list_suggestion_extra_ = std::move(reading_list_suggestion_extra);
+}
+
 void ContentSuggestion::set_notification_extra(
     std::unique_ptr<NotificationExtra> notification_extra) {
   notification_extra_ = std::move(notification_extra);