Standardize usage of virtual/override/final in content/renderer/

content/renderer/notification_provider.h

Index: content/renderer/notification_provider.h
diff --git a/content/renderer/notification_provider.h b/content/renderer/notification_provider.h
index ea31a608b33a9dd0aa609aabf11d48c0e1d3e0b1..9015515d4b06d87a8b67f5069d60bcb7385bf014 100644
--- a/content/renderer/notification_provider.h
+++ b/content/renderer/notification_provider.h
@@ -23,11 +23,11 @@ class NotificationProvider : public RenderFrameObserver,
                              public blink::WebNotificationPresenter {
  public:
   explicit NotificationProvider(RenderFrame* render_frame);
-  virtual ~NotificationProvider();
+  ~NotificationProvider() override;
 
  private:
   // RenderFrameObserver implementation.
-  virtual bool OnMessageReceived(const IPC::Message& message) override;
+  bool OnMessageReceived(const IPC::Message& message) override;
 
   // blink::WebNotificationPresenter implementation.
   virtual bool show(const blink::WebNotification& proxy);