Update {virtual,override,final} to follow C++11 style.

chrome/browser/metrics/android_metrics_provider.h

 // 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.
 
 #ifndef CHROME_BROWSER_METRICS_ANDROID_METRICS_PROVIDER_H_
 #define CHROME_BROWSER_METRICS_ANDROID_METRICS_PROVIDER_H_
 
 #include "base/basictypes.h"
 #include "chrome/browser/android/activity_type_ids.h"
 #include "components/metrics/metrics_provider.h"
 
 class PrefService;
 class PrefRegistrySimple;
 
 namespace metrics {
 class ChromeUserMetricsExtension;
 }
 
 // AndroidMetricsProvider provides Android-specific stability metrics.
 class AndroidMetricsProvider : public metrics::MetricsProvider {
  public:
   // Creates the AndroidMetricsProvider with the given |local_state|.
   explicit AndroidMetricsProvider(PrefService* local_state);
-  virtual ~AndroidMetricsProvider();
+  ~AndroidMetricsProvider() override;
 
   // metrics::MetricsProvider:
-  virtual void ProvideStabilityMetrics(
+  void ProvideStabilityMetrics(
       metrics::SystemProfileProto* system_profile_proto) override;
-  virtual void ProvideGeneralMetrics(
+  void ProvideGeneralMetrics(
       metrics::ChromeUserMetricsExtension* uma_proto) override;
 
   // Called when the Activity that the user interacts with is swapped out.
   // TODO(asvitkine): Expose a way for Android code to actually invoke this.
   void OnForegroundActivityChanged(ActivityTypeIds::Type type);
 
   // Registers local state prefs used by this class.
   static void RegisterPrefs(PrefRegistrySimple* registry);
 
  private:
   // Called to log launch and crash stats to preferences.
   void LogStabilityToPrefs();
 
   // Converts crash stats stored in the preferences into histograms.
   void ConvertStabilityPrefsToHistograms();
 
   // Weak pointer to the local state prefs store.
   PrefService* local_state_;
 
   DISALLOW_COPY_AND_ASSIGN(AndroidMetricsProvider);
 };
 
 #endif  // CHROME_BROWSER_METRICS_ANDROID_METRICS_PROVIDER_H_