Push API: Return cached registration if available.

content/browser/push_messaging/push_messaging_message_filter.h

Index: content/browser/push_messaging/push_messaging_message_filter.h
diff --git a/content/browser/push_messaging/push_messaging_message_filter.h b/content/browser/push_messaging/push_messaging_message_filter.h
index 6414cc16555da0033eb0e395d5972e6caa748f2d..a41e51f49e4de4f9cc9c2ba339a9d10a67096c60 100644
--- a/content/browser/push_messaging/push_messaging_message_filter.h
+++ b/content/browser/push_messaging/push_messaging_message_filter.h
@@ -63,6 +63,15 @@ class PushMessagingMessageFilter : public BrowserMessageFilter {
   void OnGetPermissionStatus(int request_id,
                              int64 service_worker_registration_id);
 
+  void CheckForExistingRegistration(const RegisterData& data,
+                                    const std::string& sender_id);
+
+  void DidCheckForExistingRegistration(
+      const RegisterData& data,
+      const std::string& sender_id,
+      const std::string& push_registration_id,
+      ServiceWorkerStatusCode service_worker_status);
+
   void RegisterOnUI(const RegisterData& data,
                     const std::string& sender_id);
 
@@ -91,6 +100,7 @@ class PushMessagingMessageFilter : public BrowserMessageFilter {
   void SendRegisterError(const RegisterData& data,
                          PushRegistrationStatus status);
   void SendRegisterSuccess(const RegisterData& data,
+                           PushRegistrationStatus status,
                            const GURL& push_endpoint,
                            const std::string& push_registration_id);