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

chrome/browser/media/router/media_sink.h

 // Copyright 2015 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_BROWSER_MEDIA_ROUTER_MEDIA_SINK_H_
 #define CHROME_BROWSER_MEDIA_ROUTER_MEDIA_SINK_H_
 
 #include <string>
 
 namespace media_router {
 
 // Represents a sink to which media can be routed.
 class MediaSink {
  public:
   using Id = std::string;
 
   enum IconType {
     CAST,
     CAST_AUDIO,
     CAST_AUDIO_GROUP,
     GENERIC,
     HANGOUT
   };
 
   MediaSink(const MediaSink::Id& sink_id,
             const std::string& name,
             const IconType icon_type);
 
+  MediaSink(const MediaSink& other);
+
   ~MediaSink();
 
   const MediaSink::Id& id() const { return sink_id_; }
   const std::string& name() const { return name_; }
   void set_description(const std::string& description) {
     description_ = description;
   }
   const std::string& description() const { return description_; }
   void set_domain(const std::string& domain) {
     domain_ = domain;
@@ skipping 16 matching lines @@
   // Optional domain of the MediaSink.
   std::string domain_;
 
   // The type of icon that corresponds with the MediaSink.
   IconType icon_type_;
 };
 
 }  // namespace media_router
 
 #endif  // CHROME_BROWSER_MEDIA_ROUTER_MEDIA_SINK_H_