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

components/metrics/histogram_manager.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 COMPONENTS_METRICS_HISTOGRAM_MANAGER_H_
 #define COMPONENTS_METRICS_HISTOGRAM_MANAGER_H_
 
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/lazy_instance.h"
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram_flattener.h"
 #include "base/metrics/histogram_snapshot_manager.h"
 #include "components/metrics/proto/chrome_user_metrics_extension.pb.h"
 
 namespace metrics {
 
 // TODO(mef): crbug.com/441441. Move components/metrics/histogram_manager.*
 // files into components/android/cronet.
 //
 // A HistogramManager instance is created by Android.  It is the central
 // controller for the acquisition of log data, and the automatic transmission of
 // that log data to an external server.
 class HistogramManager : public base::HistogramFlattener {
  public:
   HistogramManager();
-  ~HistogramManager();
+  ~HistogramManager() override;
 
   // Snapshot all histograms to record the delta into |uma_proto_| and then
   // returns the serialized protobuf representation of the record in |data|.
   // Returns true if it was successfully serialized.
   bool GetDeltas(std::vector<uint8>* data);
 
   // TODO(mef): Hang Histogram Manager off java object instead of singleton.
   static HistogramManager* GetInstance();
 
  private:
@@ skipping 12 matching lines @@
 
   // Stores the protocol buffer representation for this log.
   metrics::ChromeUserMetricsExtension uma_proto_;
 
   DISALLOW_COPY_AND_ASSIGN(HistogramManager);
 };
 
 }  // namespace metrics
 
 #endif  // COMPONENTS_METRICS_HISTOGRAM_MANAGER_H_