chrome: Add out-of-line copy ctors for complex classes.

chrome/common/tts_utterance_request.h

 // Copyright (c) 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.
 
 #ifndef CHROME_COMMON_TTS_UTTERANCE_REQUEST_H_
 #define CHROME_COMMON_TTS_UTTERANCE_REQUEST_H_
 
 #include <vector>
 
 #include "base/strings/string16.h"
 
 struct TtsUtteranceRequest {
   TtsUtteranceRequest();
   ~TtsUtteranceRequest();
 
   int id;
   std::string text;
   std::string lang;
   std::string voice;
   float volume;
   float rate;
   float pitch;
 };
 
 struct TtsVoice {
   TtsVoice();
+  TtsVoice(const TtsVoice& other);
   ~TtsVoice();
 
   std::string voice_uri;
   std::string name;
   std::string lang;
   bool local_service;
   bool is_default;
 };
 
 #endif  // CHROME_COMMON_TTS_UTTERANCE_REQUEST_H_