Add more out of line copy ctors for complex classes.

remoting/protocol/client_authentication_config.h

 // Copyright 2016 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 REMOTING_PROTOCOL_CLIENT_AUTHENTICATION_CONFIG_H_
 #define REMOTING_PROTOCOL_CLIENT_AUTHENTICATION_CONFIG_H_
 
 #include <string>
 
 #include "base/callback.h"
@@ skipping 22 matching lines @@
 // |token_fetched_callback| is called when the client authentication ends, on
 // the same thread on which FetchThirdPartyTokenCallback was originally called.
 typedef base::Callback<void(
     const std::string& token_url,
     const std::string& scope,
     const ThirdPartyTokenFetchedCallback& token_fetched_callback)>
     FetchThirdPartyTokenCallback;
 
 struct ClientAuthenticationConfig {
   ClientAuthenticationConfig();
+  ClientAuthenticationConfig(const ClientAuthenticationConfig& other);
   ~ClientAuthenticationConfig();
 
   // Used for all authenticators.
   std::string host_id;
 
   // Used for pairing authenticators
   std::string pairing_client_id;
   std::string pairing_secret;
 
   // Used for shared secret authenticators.
   FetchSecretCallback fetch_secret_callback;
 
   // Used for third party authenticators.
   FetchThirdPartyTokenCallback fetch_third_party_token_callback;
 };
 
 }  // namespace protocol
 }  // namespace remoting
 
 #endif  // REMOTING_PROTOCOL_CLIENT_AUTHENTICATION_CONFIG_H_