Rename VisitDatabaseObserver to HistoryServiceObserver

chrome/browser/prerender/prerender_local_predictor.h

Index: chrome/browser/prerender/prerender_local_predictor.h
diff --git a/chrome/browser/prerender/prerender_local_predictor.h b/chrome/browser/prerender/prerender_local_predictor.h
index a0e9fcd3fd2cffe8728a9f78ac9d1a9a5eb28873..2d9074b41644cc227276c6aec5eeb4d3b3531377 100644
--- a/chrome/browser/prerender/prerender_local_predictor.h
+++ b/chrome/browser/prerender/prerender_local_predictor.h
@@ -13,6 +13,7 @@
 #include "base/memory/weak_ptr.h"
 #include "base/task/cancelable_task_tracker.h"
 #include "base/timer/timer.h"
+#include "chrome/browser/history/history_service.h"
 #include "chrome/browser/history/visit_database.h"
 #include "content/public/browser/session_storage_namespace.h"
 #include "net/url_request/url_fetcher_delegate.h"
@@ -41,7 +42,7 @@ class PrerenderManager;
 // predictions.
 // At this point, the class is not actually creating prerenders, but just
 // recording timing stats about the effect prerendering would have.
-class PrerenderLocalPredictor : public history::VisitDatabaseObserver,
+class PrerenderLocalPredictor : public HistoryService::Observer,
                                 public net::URLFetcherDelegate {
  public:
   struct LocalPredictorURLInfo;
@@ -156,7 +157,7 @@ class PrerenderLocalPredictor : public history::VisitDatabaseObserver,
 
   void Shutdown();
 
-  // history::VisitDatabaseObserver implementation
+  // HistoryService::Observer implementation
   virtual void OnAddVisit(const history::BriefVisitInfo& info) override;
 
   void OnGetInitialVisitHistory(
@@ -219,8 +220,8 @@ class PrerenderLocalPredictor : public history::VisitDatabaseObserver,
   static const int kInitDelayMs = 5 * 1000;
 
   // Whether we're registered with the history service as a
-  // history::VisitDatabaseObserver.
-  bool is_visit_database_observer_;
+  // HistoryService::Observer.
+  bool is_history_service_observer_;
 
   base::CancelableTaskTracker history_db_tracker_;