Update {virtual,override} to follow C++11 style in chrome.

chrome/browser/speech/tts_win.cc

Index: chrome/browser/speech/tts_win.cc
diff --git a/chrome/browser/speech/tts_win.cc b/chrome/browser/speech/tts_win.cc
index 2422bedcf8d1b53ea2162c05e25b2b158c98aa55..c711f9e8f1ce8dc679742aec80b8bb5e44923202 100644
--- a/chrome/browser/speech/tts_win.cc
+++ b/chrome/browser/speech/tts_win.cc
@@ -15,26 +15,26 @@
 
 class TtsPlatformImplWin : public TtsPlatformImpl {
  public:
-  virtual bool PlatformImplAvailable() {
+  bool PlatformImplAvailable() override {
     return true;
   }
 
-  virtual bool Speak(
+  bool Speak(
       int utterance_id,
       const std::string& utterance,
       const std::string& lang,
       const VoiceData& voice,
-      const UtteranceContinuousParameters& params);
+      const UtteranceContinuousParameters& params) override;
 
-  virtual bool StopSpeaking();
+  bool StopSpeaking() override;
 
-  virtual void Pause();
+  void Pause() override;
 
-  virtual void Resume();
+  void Resume() override;
 
-  virtual bool IsSpeaking();
+  bool IsSpeaking() override;
 
-  virtual void GetVoices(std::vector<VoiceData>* out_voices) override;
+  void GetVoices(std::vector<VoiceData>* out_voices) override;
 
   // Get the single instance of this class.
   static TtsPlatformImplWin* GetInstance();
@@ -43,7 +43,7 @@ class TtsPlatformImplWin : public TtsPlatformImpl {
 
  private:
   TtsPlatformImplWin();
-  virtual ~TtsPlatformImplWin() {}
+  ~TtsPlatformImplWin() override {}
 
   void OnSpeechEvent();