Support action button to fetch more content suggestions

components/ntp_snippets/content_suggestions_service.h

Index: components/ntp_snippets/content_suggestions_service.h
diff --git a/components/ntp_snippets/content_suggestions_service.h b/components/ntp_snippets/content_suggestions_service.h
index ad7f8a9f7c6a126e9636b004316c297b4066995f..6f5ab397320907c02caa58a7487a1d2f6813c664 100644
--- a/components/ntp_snippets/content_suggestions_service.h
+++ b/components/ntp_snippets/content_suggestions_service.h
@@ -88,6 +88,11 @@ class ContentSuggestionsService : public KeyedService,
   const std::vector<ContentSuggestion>& GetSuggestionsForCategory(
       Category category) const;
 
+  // Triggers a fetch for new suggestions (over the network, for example) for
+  // the given |category|. This must be initiated by the user (e.g. by clicking
+  // the a "More" button).

[Marc Treib, 2016/08/10 09:40:31]

nit: remove "a"

[Philipp Keck, 2016/08/10 13:14:47]

Done.

+  void FetchMoreSuggestions(Category category);
+
   // Fetches the image for the suggestion with the given |suggestion_id| and
   // runs the |callback|. If that suggestion doesn't exist or the fetch fails,
   // the callback gets an empty image. The callback will not be called