Standardize usage of virtual/override/final in mojo/

mojo/services/test_service/test_request_tracker_impl.h

Index: mojo/services/test_service/test_request_tracker_impl.h
diff --git a/mojo/services/test_service/test_request_tracker_impl.h b/mojo/services/test_service/test_request_tracker_impl.h
index 736cc70ea20338e49fe96db5150996d991a5295a..d2104dc7a67b16a9b5e4a8738c21bced13ef2e29 100644
--- a/mojo/services/test_service/test_request_tracker_impl.h
+++ b/mojo/services/test_service/test_request_tracker_impl.h
@@ -28,13 +28,13 @@ struct TrackingContext {
 class TestRequestTrackerImpl : public InterfaceImpl<TestRequestTracker> {
  public:
   explicit TestRequestTrackerImpl(TrackingContext* context);
-  virtual ~TestRequestTrackerImpl();
+  ~TestRequestTrackerImpl() override;
 
   // TestRequestTracker.
-  virtual void RecordStats(uint64_t client_id, ServiceStatsPtr stats) override;
+  void RecordStats(uint64_t client_id, ServiceStatsPtr stats) override;
 
   // InterfaceImpl override.
-  virtual void OnConnectionEstablished() override;
+  void OnConnectionEstablished() override;
 
  private:
   void UploaderNameCallback(uint64_t id, const mojo::String& name);
@@ -47,12 +47,11 @@ class TestTrackedRequestServiceImpl
     : public InterfaceImpl<TestTrackedRequestService> {
  public:
   explicit TestTrackedRequestServiceImpl(TrackingContext* context);
-  virtual ~TestTrackedRequestServiceImpl();
+  ~TestTrackedRequestServiceImpl() override;
 
   // |TestTrackedRequestService| implementation.
-  virtual void GetReport(
-      const mojo::Callback<void(mojo::Array<ServiceReportPtr>)>& callback)
-      override;
+  void GetReport(const mojo::Callback<void(mojo::Array<ServiceReportPtr>)>&
+                     callback) override;
 
  private:
   TrackingContext* context_;