Standardize usage of virtual/override/final specifiers.

extensions/shell/browser/shell_runtime_api_delegate.h

Index: extensions/shell/browser/shell_runtime_api_delegate.h
diff --git a/extensions/shell/browser/shell_runtime_api_delegate.h b/extensions/shell/browser/shell_runtime_api_delegate.h
index 92bb1ac5947dae7d47b78bb8ad1b26a68427a22a..816423b09745922808163b1521200bc9c21c2681 100644
--- a/extensions/shell/browser/shell_runtime_api_delegate.h
+++ b/extensions/shell/browser/shell_runtime_api_delegate.h
@@ -13,19 +13,19 @@ namespace extensions {
 class ShellRuntimeAPIDelegate : public RuntimeAPIDelegate {
  public:
   ShellRuntimeAPIDelegate();
-  virtual ~ShellRuntimeAPIDelegate();
+  ~ShellRuntimeAPIDelegate() override;
 
   // RuntimeAPIDelegate implementation.
-  virtual void AddUpdateObserver(UpdateObserver* observer) override;
-  virtual void RemoveUpdateObserver(UpdateObserver* observer) override;
-  virtual base::Version GetPreviousExtensionVersion(
+  void AddUpdateObserver(UpdateObserver* observer) override;
+  void RemoveUpdateObserver(UpdateObserver* observer) override;
+  base::Version GetPreviousExtensionVersion(
       const Extension* extension) override;
-  virtual void ReloadExtension(const std::string& extension_id) override;
-  virtual bool CheckForUpdates(const std::string& extension_id,
-                               const UpdateCheckCallback& callback) override;
-  virtual void OpenURL(const GURL& uninstall_url) override;
-  virtual bool GetPlatformInfo(core_api::runtime::PlatformInfo* info) override;
-  virtual bool RestartDevice(std::string* error_message) override;
+  void ReloadExtension(const std::string& extension_id) override;
+  bool CheckForUpdates(const std::string& extension_id,
+                       const UpdateCheckCallback& callback) override;
+  void OpenURL(const GURL& uninstall_url) override;
+  bool GetPlatformInfo(core_api::runtime::PlatformInfo* info) override;
+  bool RestartDevice(std::string* error_message) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ShellRuntimeAPIDelegate);