Populate .current when navigator.serviceWorker is accessed

content/browser/service_worker/service_worker_handle.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 CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_HANDLE_H_
 #define CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_HANDLE_H_
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 53 matching lines @@
                                       int line_number,
                                       const GURL& source_url) OVERRIDE;
   virtual void OnVersionStateChanged(ServiceWorkerVersion* version) OVERRIDE;
 
   ServiceWorkerObjectInfo GetObjectInfo();
 
   ServiceWorkerRegistration* registration() { return registration_.get(); }
   ServiceWorkerVersion* version() { return version_.get(); }
   int handle_id() const { return handle_id_; }
 
+  bool HasNoRefCount() const { return ref_count_ <= 0; }
+  void IncrementRefCount();
+  void DecrementRefCount();
+
  private:
   base::WeakPtr<ServiceWorkerContextCore> context_;
   IPC::Sender* sender_;  // Not owned, it should always outlive this.
   const int thread_id_;
   const int handle_id_;
+  int ref_count_;  // Created with 1.
   scoped_refptr<ServiceWorkerRegistration> registration_;
   scoped_refptr<ServiceWorkerVersion> version_;
 
   DISALLOW_COPY_AND_ASSIGN(ServiceWorkerHandle);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_HANDLE_H_