Standardize usage of virtual/override/final in components/

components/domain_reliability/test_util.cc

Index: components/domain_reliability/test_util.cc
diff --git a/components/domain_reliability/test_util.cc b/components/domain_reliability/test_util.cc
index 49d9807d1773449c98c5874bee3c9e0b7c23e412..b541bf76048ece2a627cf07c9693fa936b2979ff 100644
--- a/components/domain_reliability/test_util.cc
+++ b/components/domain_reliability/test_util.cc
@@ -24,12 +24,12 @@ class MockTimer : public MockableTime::Timer {
     DCHECK(time);
   }
 
-  virtual ~MockTimer() {}
+  ~MockTimer() override {}
 
   // MockableTime::Timer implementation:
-  virtual void Start(const tracked_objects::Location& posted_from,
-                     base::TimeDelta delay,
-                     const base::Closure& user_task) override {
+  void Start(const tracked_objects::Location& posted_from,
+             base::TimeDelta delay,
+             const base::Closure& user_task) override {
     DCHECK(!user_task.is_null());
 
     if (running_)
@@ -42,14 +42,14 @@ class MockTimer : public MockableTime::Timer {
                    callback_sequence_number_));
   }
 
-  virtual void Stop() override {
+  void Stop() override {
     if (running_) {
       ++callback_sequence_number_;
       running_ = false;
     }
   }
 
-  virtual bool IsRunning() override { return running_; }
+  bool IsRunning() override { return running_; }
 
  private:
   void OnDelayPassed(int expected_callback_sequence_number) {