Add PrerenderLocalPredictor, which will eventually perform

chrome/browser/history/history_backend.h

Index: chrome/browser/history/history_backend.h
===================================================================
--- chrome/browser/history/history_backend.h	(revision 133528)
+++ chrome/browser/history/history_backend.h	(working copy)
@@ -91,6 +91,9 @@
 
     // Tell TopSites to start reading thumbnails from the ThumbnailsDB.
     virtual void StartTopSitesMigration(int backend_id) = 0;
+
+    virtual void NotifyVisitDBObserversOnAddVisit(
+        const history::BriefVisitInfo& info) = 0;
   };
 
   // Init must be called to complete object creation. This object can be
@@ -588,6 +591,9 @@
   // and true if returned on success, otherwise false is returned.
   bool GetFaviconFromDB(FaviconID favicon_id, FaviconData* favicon);
 
+  // Notify any observers of an addition to the visit database.
+  void NotifyVisitObservers(const VisitRow& visit);
+
   // Data ----------------------------------------------------------------------
 
   // Delegate. See the class definition above for more information. This will