Standardize usage of virtual/override/final specifiers.

chrome/browser/search/most_visited_iframe_source_unittest.cc

 // Copyright 2013 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.
 
 #include "base/bind.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/statistics_recorder.h"
 #include "base/strings/stringprintf.h"
 #include "chrome/browser/search/most_visited_iframe_source.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 class MostVisitedIframeSourceTest : public testing::Test {
  public:
   void ExpectNullData(base::RefCountedMemory* data) {
     EXPECT_EQ(NULL, data);
   }
 
  protected:
   MostVisitedIframeSource* source() { return source_.get(); }
 
  private:
-  virtual void SetUp() { source_.reset(new MostVisitedIframeSource()); }
+  void SetUp() override { source_.reset(new MostVisitedIframeSource()); }
 
   scoped_ptr<MostVisitedIframeSource> source_;
 };