Add OVERRIDE to net/.

net/disk_cache/stats_histogram.h

Index: net/disk_cache/stats_histogram.h
diff --git a/net/disk_cache/stats_histogram.h b/net/disk_cache/stats_histogram.h
index 318a8bce77483bec4292dde7a2dd3aff139b13dc..9d44545b3768030bb2871a523a695857619ab379 100644
--- a/net/disk_cache/stats_histogram.h
+++ b/net/disk_cache/stats_histogram.h
@@ -40,11 +40,12 @@ class StatsHistogram : public base::Histogram {
   // We'll be reporting data from the given set of cache stats.
   bool Init(const Stats* stats);
 
-  virtual Sample ranges(size_t i) const;
-  virtual size_t bucket_count() const;
-  virtual void SnapshotSample(SampleSet* sample) const;
-  virtual Inconsistencies FindCorruption(const SampleSet& snapshot) const;
-  virtual uint32 CalculateRangeChecksum() const;
+  virtual Sample ranges(size_t i) const OVERRIDE;
+  virtual size_t bucket_count() const OVERRIDE;
+  virtual void SnapshotSample(SampleSet* sample) const OVERRIDE;
+  virtual Inconsistencies FindCorruption(
+      const SampleSet& snapshot) const OVERRIDE;
+  virtual uint32 CalculateRangeChecksum() const OVERRIDE;
 
  private:
   bool init_;