Rename VisitDatabaseObserver to HistoryServiceObserver

chrome/browser/history/in_memory_history_backend.h

Index: chrome/browser/history/in_memory_history_backend.h
diff --git a/chrome/browser/history/in_memory_history_backend.h b/chrome/browser/history/in_memory_history_backend.h
index 56f378a7abc17412b0deabefed84a3d26e137a31..2312a3e275f7e263b108bea0bc2d3fd08c518c21 100644
--- a/chrome/browser/history/in_memory_history_backend.h
+++ b/chrome/browser/history/in_memory_history_backend.h
@@ -25,12 +25,11 @@
 #include "base/basictypes.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/scoped_ptr.h"
-#include "components/history/core/browser/history_service_observer.h"
+#include "chrome/browser/history/history_service.h"
 #include "components/history/core/browser/keyword_id.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
-class HistoryService;
 class Profile;
 
 namespace base {
@@ -47,7 +46,7 @@ class URLRow;
 struct URLsDeletedDetails;
 struct URLsModifiedDetails;
 
-class InMemoryHistoryBackend : public HistoryServiceObserver,
+class InMemoryHistoryBackend : public HistoryService::Observer,
                                public content::NotificationObserver {
  public:
   InMemoryHistoryBackend();
@@ -73,7 +72,7 @@ class InMemoryHistoryBackend : public HistoryServiceObserver,
     return db_.get();
   }
 
-  // HistoryServiceObserver:
+  // HistoryService::Observer:
   virtual void OnURLVisited(ui::PageTransition transition,
                             const URLRow& row,
                             const RedirectList& redirects,