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

chrome/renderer/content_settings_observer.h

Index: chrome/renderer/content_settings_observer.h
diff --git a/chrome/renderer/content_settings_observer.h b/chrome/renderer/content_settings_observer.h
index 4e084fb201f58cdd67f9597ff2d3dd4cfddbb8a4..ba9e2fff15a5be965b2384deaf26fecc24e77c66 100644
--- a/chrome/renderer/content_settings_observer.h
+++ b/chrome/renderer/content_settings_observer.h
@@ -35,7 +35,7 @@ class ContentSettingsObserver
  public:
   ContentSettingsObserver(content::RenderFrame* render_frame,
                           extensions::Dispatcher* extension_dispatcher);
-  virtual ~ContentSettingsObserver();
+  ~ContentSettingsObserver() override;
 
   // Sets the content setting rules which back |AllowImage()|, |AllowScript()|,
   // and |AllowScriptFromSource()|. |content_setting_rules| must outlive this
@@ -88,8 +88,8 @@ class ContentSettingsObserver
   FRIEND_TEST_ALL_PREFIXES(ChromeRenderViewTest, PluginsTemporarilyAllowed);
 
   // RenderFrameObserver implementation.
-  virtual bool OnMessageReceived(const IPC::Message& message) override;
-  virtual void DidCommitProvisionalLoad(bool is_new_navigation) override;
+  bool OnMessageReceived(const IPC::Message& message) override;
+  void DidCommitProvisionalLoad(bool is_new_navigation) override;
 
   // Message handlers.
   void OnLoadBlockedPlugins(const std::string& identifier);