Persist Instance ID data to GCM store.

google_apis/gcm/engine/gcm_store.h

Index: google_apis/gcm/engine/gcm_store.h
diff --git a/google_apis/gcm/engine/gcm_store.h b/google_apis/gcm/engine/gcm_store.h
index 0cbb0857243840637279f8104781527316953221..cfefe914b45ddc4b86d1fac8a65b39a5dd8dc075 100644
--- a/google_apis/gcm/engine/gcm_store.h
+++ b/google_apis/gcm/engine/gcm_store.h
@@ -57,6 +57,7 @@ class GCM_EXPORT GCMStore {
     AccountMappings account_mappings;
     base::Time last_token_fetch_time;
     std::map<std::string, int> heartbeat_intervals;
+    std::map<std::string, std::string> instance_id_data;
   };
 
   typedef std::vector<std::string> PersistentIdList;
@@ -141,6 +142,13 @@ class GCM_EXPORT GCMStore {
   virtual void RemoveHeartbeatInterval(const std::string& scope,
                                        const UpdateCallback& callback) = 0;
 
+  // Instance ID data.
+  virtual void AddInstanceIDData(const std::string& app_id,
+                                 const std::string& instance_id_data,
+                                 const UpdateCallback& callback) = 0;
+  virtual void RemoveInstanceIDData(const std::string& app_id,
+                                    const UpdateCallback& callback) = 0;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(GCMStore);
 };