[GCM] Add app handler support for connection events

components/gcm_driver/gcm_app_handler.h

Index: components/gcm_driver/gcm_app_handler.h
diff --git a/components/gcm_driver/gcm_app_handler.h b/components/gcm_driver/gcm_app_handler.h
index 31bab34d8905a19e5d36fd75ac13fc25dd642a13..b4b497e3975fa4fa5fb408f126b4746c8b760025 100644
--- a/components/gcm_driver/gcm_app_handler.h
+++ b/components/gcm_driver/gcm_app_handler.h
@@ -16,8 +16,8 @@ namespace gcm {
 // app.
 class GCMAppHandler {
  public:
-  GCMAppHandler() {}
-  virtual ~GCMAppHandler() {}
+  GCMAppHandler();
+  virtual ~GCMAppHandler();
 
   // Called to do all the cleanup when GCM is shutting down.
   // In the case that multiple apps share the same app handler, it should be
@@ -35,6 +35,16 @@ class GCMAppHandler {
   virtual void OnSendError(
       const std::string& app_id,
       const GCMClient::SendErrorDetails& send_error_details) = 0;
+
+  // Called when a new connection is established and a successful handshake
+  // has been performed. Note that |ip_endpoint| is only set if available for
+  // the current platform.
+  // Default implementation does nothing.
+  virtual void OnConnected(const net::IPEndPoint& ip_endpoint);
+
+  // Called when the connection is interrupted.
+  // Default implementation does nothing.
+  virtual void OnDisconnected();
 };
 
 }  // namespace gcm