Standardize usage of virtual/override/final specifiers in dbus/.

dbus/test_service.h

Index: dbus/test_service.h
diff --git a/dbus/test_service.h b/dbus/test_service.h
index cc7d5211f915d6a034fed2ed310b7101a8d42392..5f215d3f266a7cff24e0680fa51bde77e940a6c4 100644
--- a/dbus/test_service.h
+++ b/dbus/test_service.h
@@ -46,7 +46,7 @@ class TestService : public base::Thread {
   static const int kNumMethodsToExport;
 
   explicit TestService(const Options& options);
-  virtual ~TestService();
+  ~TestService() override;
 
   // Starts the service in a separate thread.
   // Returns true if the thread is started successfully.
@@ -106,7 +106,7 @@ class TestService : public base::Thread {
                   bool success);
 
   // base::Thread override.
-  virtual void Run(base::MessageLoop* message_loop) override;
+  void Run(base::MessageLoop* message_loop) override;
 
   //
   // Exported methods.