[GCM] Extracting GCMConnectionObserver from GCMAppHandler

components/gcm_driver/gcm_driver.h

 // Copyright 2014 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_GCM_DRIVER_H_
 #define COMPONENTS_GCM_DRIVER_GCM_DRIVER_H_
 
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/threading/thread_checker.h"
 #include "components/gcm_driver/default_gcm_app_handler.h"
 #include "components/gcm_driver/gcm_client.h"
 
 namespace gcm {
 
 class GCMAppHandler;
+class GCMConnectionObserver;
 struct AccountMapping;
 
 // Bridge between GCM users in Chrome and the platform-specific implementation.
 class GCMDriver {
  public:
   typedef std::map<std::string, GCMAppHandler*> GCMAppHandlerMap;
   typedef base::Callback<void(const std::string& registration_id,
                               GCMClient::Result result)> RegisterCallback;
   typedef base::Callback<void(const std::string& message_id,
                               GCMClient::Result result)> SendCallback;
@@ skipping 50 matching lines @@
 
   // Adds a handler for a given app.
   virtual void AddAppHandler(const std::string& app_id, GCMAppHandler* handler);
 
   // Remove the handler for a given app.
   virtual void RemoveAppHandler(const std::string& app_id);
 
   // Returns the handler for the given app.
   GCMAppHandler* GetAppHandler(const std::string& app_id);
 
+  // Adds a connection state observer.
+  virtual void AddConnectionObserver(GCMConnectionObserver* observer) = 0;
+
+  // Removes a connection state observer.
+  virtual void RemoveConnectionObserver(GCMConnectionObserver* observer) = 0;
+
   // Enables/disables GCM service.
   virtual void Enable() = 0;
   virtual void Disable() = 0;
 
   // For testing purpose. Always NULL on Android.
   virtual GCMClient* GetGCMClientForTesting() const = 0;
 
   // Returns true if the service was started.
   virtual bool IsStarted() const = 0;
 
@@ skipping 71 matching lines @@
 
   // The default handler when no app handler can be found in the map.
   DefaultGCMAppHandler default_app_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(GCMDriver);
 };
 
 }  // namespace gcm
 
 #endif  // COMPONENTS_GCM_DRIVER_GCM_DRIVER_H_