Standardize usage of virtual/override/final specifiers.

components/metrics/metrics_service_unittest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/metrics/metrics_service.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 81 matching lines @@
   MetricsServiceTest() : is_metrics_reporting_enabled_(false) {
     MetricsService::RegisterPrefs(testing_local_state_.registry());
     metrics_state_manager_ = MetricsStateManager::Create(
         GetLocalState(),
         base::Bind(&MetricsServiceTest::is_metrics_reporting_enabled,
                    base::Unretained(this)),
         base::Bind(&StoreNoClientInfoBackup),
         base::Bind(&ReturnNoBackup));
   }
 
-  virtual ~MetricsServiceTest() {
+  ~MetricsServiceTest() override {
     MetricsService::SetExecutionPhase(MetricsService::UNINITIALIZED_PHASE,
                                       GetLocalState());
   }
 
   MetricsStateManager* GetMetricsStateManager() {
     return metrics_state_manager_.get();
   }
 
   PrefService* GetLocalState() { return &testing_local_state_; }
 
@@ skipping 238 matching lines @@
           "clientID", 1, MetricsLog::ONGOING_LOG, &client, GetLocalState())));
   service.GetCurrentSyntheticFieldTrials(&synthetic_trials);
   EXPECT_EQ(3U, synthetic_trials.size());
   EXPECT_TRUE(HasSyntheticTrial(synthetic_trials, "TestTrial1", "Group2"));
   EXPECT_TRUE(HasSyntheticTrial(synthetic_trials, "TestTrial2", "Group2"));
   EXPECT_TRUE(HasSyntheticTrial(synthetic_trials, "TestTrial3", "Group3"));
   service.log_manager_.FinishCurrentLog();
 }
 
 }  // namespace metrics