Add support for components/ntp_tiles in InstantService

components/ntp_tiles/most_visited_sites.h

Index: components/ntp_tiles/most_visited_sites.h
diff --git a/components/ntp_tiles/most_visited_sites.h b/components/ntp_tiles/most_visited_sites.h
index 158d0d06e8575e618a49baf6ba77906c04dda0ec..d097b1bc469974c307cf27518061f3737470e98d 100644
--- a/components/ntp_tiles/most_visited_sites.h
+++ b/components/ntp_tiles/most_visited_sites.h
@@ -102,11 +102,17 @@ class MostVisitedSites : public history::TopSitesObserver,
 
   ~MostVisitedSites() override;
 
+  // Sets the observer, and immediately fetches the current suggestions.
   // Does not take ownership of |observer|, which must outlive this object and
   // must not be null.
   void SetMostVisitedURLsObserver(Observer* observer, int num_sites);
 
+  // Requests an asynchronous refresh of the suggestions. Notifies the observer
+  // once the request completes.
+  void Refresh();
+
   void AddOrRemoveBlacklistedUrl(const GURL& url, bool add_url);
+  void ClearBlacklistedUrls();
 
   // MostVisitedSitesSupervisor::Observer implementation.
   void OnBlockedSitesChanged() override;