Remove NOTIFICATION_HISTORY_URLS_DELETED

chrome/browser/extensions/api/history/history_api.h

Index: chrome/browser/extensions/api/history/history_api.h
diff --git a/chrome/browser/extensions/api/history/history_api.h b/chrome/browser/extensions/api/history/history_api.h
index ccae66fb0c4872e09b8ec589a9a1449b930a8223..b53bdba05dc1df9ea3a6a36aab282c811d0d8ccb 100644
--- a/chrome/browser/extensions/api/history/history_api.h
+++ b/chrome/browser/extensions/api/history/history_api.h
@@ -16,7 +16,6 @@
 #include "chrome/browser/history/history_service.h"
 #include "chrome/common/extensions/api/history.h"
 #include "components/history/core/browser/history_service_observer.h"
-#include "content/public/browser/notification_registrar.h"
 #include "extensions/browser/browser_context_keyed_api_factory.h"
 #include "extensions/browser/event_router.h"
 
@@ -28,24 +27,21 @@ namespace extensions {
 
 // Observes History service and routes the notifications as events to the
 // extension system.
-class HistoryEventRouter : public content::NotificationObserver,
-                           public history::HistoryServiceObserver {
+class HistoryEventRouter : public history::HistoryServiceObserver {
  public:
   HistoryEventRouter(Profile* profile, HistoryService* history_service);
   ~HistoryEventRouter() override;
 
  private:
-  // content::NotificationObserver::Observe.
-  void Observe(int type,
-               const content::NotificationSource& source,
-               const content::NotificationDetails& details) override;
-
   // history::HistoryServiceObserver.
   void OnURLVisited(HistoryService* history_service,
                     ui::PageTransition transition,
                     const history::URLRow& row,
                     const history::RedirectList& redirects,
                     base::Time visit_time) override;
+  void OnURLsDeleted(
+      HistoryService* history_service,
+      const history::URLsDeletedDetails& deleted_details) override;
 
   void HistoryUrlsRemoved(Profile* profile,
                           const history::URLsDeletedDetails* details);
@@ -54,8 +50,6 @@ class HistoryEventRouter : public content::NotificationObserver,
                      const std::string& event_name,
                      scoped_ptr<base::ListValue> event_args);
 
-  // Used for tracking registrations to history service notifications.
-  content::NotificationRegistrar registrar_;
   Profile* profile_;
   ScopedObserver<HistoryService, HistoryServiceObserver>
       history_service_observer_;