Standardize usage of virtual/override/final in components/

components/component_updater/default_component_installer.h

Index: components/component_updater/default_component_installer.h
diff --git a/components/component_updater/default_component_installer.h b/components/component_updater/default_component_installer.h
index 345c3dd470e8e8d5eacc7b9b0f57b8e3fd1d4126..3946ab390ffcbebd6e0a1faa99a7a8f4501c1d83 100644
--- a/components/component_updater/default_component_installer.h
+++ b/components/component_updater/default_component_installer.h
@@ -91,13 +91,13 @@ class DefaultComponentInstaller : public ComponentInstaller {
   void Register(ComponentUpdateService* cus);
 
   // Overridden from ComponentInstaller:
-  virtual void OnUpdateError(int error) override;
-  virtual bool Install(const base::DictionaryValue& manifest,
-                       const base::FilePath& unpack_path) override;
-  virtual bool GetInstalledFile(const std::string& file,
-                                base::FilePath* installed_file) override;
+  void OnUpdateError(int error) override;
+  bool Install(const base::DictionaryValue& manifest,
+               const base::FilePath& unpack_path) override;
+  bool GetInstalledFile(const std::string& file,
+                        base::FilePath* installed_file) override;
 
-  virtual ~DefaultComponentInstaller();
+  ~DefaultComponentInstaller() override;
 
  private:
   base::FilePath GetInstallDirectory();