[GCM] Extracting GCMConnectionObserver from GCMAppHandler

components/gcm_driver/gcm_driver.h

Index: components/gcm_driver/gcm_driver.h
diff --git a/components/gcm_driver/gcm_driver.h b/components/gcm_driver/gcm_driver.h
index c4646edd096b7ab9a1bd1b4f91b2b1234a59b1b7..c10d9f16769ddfc445e1ce1c9a2a16b7fad7469a 100644
--- a/components/gcm_driver/gcm_driver.h
+++ b/components/gcm_driver/gcm_driver.h
@@ -18,6 +18,7 @@
 namespace gcm {
 
 class GCMAppHandler;
+class GCMConnectionObserver;
 struct AccountMapping;
 
 // Bridge between GCM users in Chrome and the platform-specific implementation.
@@ -88,6 +89,12 @@ class GCMDriver {
   // 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;