Add OVERRIDE to chrome/common/ and nacl/.

chrome/common/metrics_helpers.h

 // Copyright (c) 2011 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.
 
 // This file defines a set of user experience metrics data recorded by
 // the MetricsService.  This is the unit of data that is sent to the server.
 
 #ifndef CHROME_COMMON_METRICS_HELPERS_H_
 #define CHROME_COMMON_METRICS_HELPERS_H_
 #pragma once
@@ skipping 218 matching lines @@
   // Called when we close a log.
   void RecordCurrentHistograms();
 
   // Manager for the various in-flight logs.
   MetricsLogManager log_manager_;
 
  private:
   // HistogramSender interface (override) methods.
   virtual void TransmitHistogramDelta(
       const base::Histogram& histogram,
-      const base::Histogram::SampleSet& snapshot);
-  virtual void InconsistencyDetected(int problem);
-  virtual void UniqueInconsistencyDetected(int problem);
-  virtual void SnapshotProblemResolved(int amount);
+      const base::Histogram::SampleSet& snapshot) OVERRIDE;
+  virtual void InconsistencyDetected(int problem) OVERRIDE;
+  virtual void UniqueInconsistencyDetected(int problem) OVERRIDE;
+  virtual void SnapshotProblemResolved(int amount) OVERRIDE;
 
   DISALLOW_COPY_AND_ASSIGN(MetricsServiceBase);
 };
 
 #endif  // CHROME_COMMON_METRICS_HELPERS_H_