replace OVERRIDE and FINAL with override and final in base/

base/metrics/histogram_samples.cc

Index: base/metrics/histogram_samples.cc
diff --git a/base/metrics/histogram_samples.cc b/base/metrics/histogram_samples.cc
index 2319ed1572f2af2449be2b452e43ccc5b37452f6..26c2aeb087c3f2d91a9921aadfdf0c64e5c69dfe 100644
--- a/base/metrics/histogram_samples.cc
+++ b/base/metrics/histogram_samples.cc
@@ -15,11 +15,11 @@ class SampleCountPickleIterator : public SampleCountIterator {
  public:
   explicit SampleCountPickleIterator(PickleIterator* iter);
 
-  virtual bool Done() const OVERRIDE;
-  virtual void Next() OVERRIDE;
+  virtual bool Done() const override;
+  virtual void Next() override;
   virtual void Get(HistogramBase::Sample* min,
                    HistogramBase::Sample* max,
-                   HistogramBase::Count* count) const OVERRIDE;
+                   HistogramBase::Count* count) const override;
  private:
   PickleIterator* const iter_;