Add support for GCM subtypes to desktop Instance ID implementation

components/gcm_driver/registration_info.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 COMPONENTS_GCM_DRIVER_REGISTRATION_INFO_H_
 #define COMPONENTS_GCM_DRIVER_REGISTRATION_INFO_H_
 
 #include <map>
 #include <memory>
 #include <string>
@@ skipping 87 matching lines @@
   // Entity that is authorized to access resources associated with the Instance
   // ID. It can be another Instance ID or a project ID assigned by the Google
   // API Console.
   std::string authorized_entity;
 
   // Authorized actions that the authorized entity can take.
   // E.g. for sending GCM messages, 'GCM' scope should be used.
   std::string scope;
 
   // Allows including a small number of string key/value pairs that will be
-  // associated with the token and may be used in processing the request.
+  // associated with the token and may be used in processing the request. These
+  // are not serialized/deserialized.
   std::map<std::string, std::string> options;
 };
 
 struct RegistrationInfoComparer {
   bool operator()(const linked_ptr<RegistrationInfo>& a,
                   const linked_ptr<RegistrationInfo>& b) const;
 };
 
 // Collection of registration info.
 // Map from RegistrationInfo instance to registration ID.
 typedef std::map<linked_ptr<RegistrationInfo>,
                 std::string,
                 RegistrationInfoComparer> RegistrationInfoMap;
 
 // Returns true if a GCM registration for |app_id| exists in |map|.
 bool ExistsGCMRegistrationInMap(const RegistrationInfoMap& map,
                                 const std::string& app_id);
 
 }  // namespace gcm
 
 #endif  // COMPONENTS_GCM_DRIVER_REGISTRATION_INFO_H_