[WIP] [service worker] Fix detach controller and fallback to network mechanism

content/child/service_worker/service_worker_handle_reference.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_CHILD_SERVICE_WORKER_SERVICE_WORKER_HANDLE_REFERENCE_H_
 #define CONTENT_CHILD_SERVICE_WORKER_SERVICE_WORKER_HANDLE_REFERENCE_H_
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "content/common/content_export.h"
 #include "content/common/service_worker/service_worker_types.h"
 
 namespace content {
 
 class ThreadSafeSender;
 
 // Represents an interprocess reference to ServiceWorkerHandle managed in the
 // browser process. The constructor and destructor sends a message to increment
 // or decrement the reference count to the browser process.
 class CONTENT_EXPORT ServiceWorkerHandleReference {
  public:
-  // Creates a new ServiceWorkerHandleReference and increments ref-count.
+  // Creates a new ServiceWorkerHandleReference and increments ref-count. If
+  // the handle id is kInvalidServiceWorkerHandleId, returns null instead.
   static scoped_ptr<ServiceWorkerHandleReference> Create(
       const ServiceWorkerObjectInfo& info,
       ThreadSafeSender* sender);
 
-  // Creates a new ServiceWorkerHandleReference by adopting a ref-count.
+  // Creates a new ServiceWorkerHandleReference by adopting a ref-count. If
+  // the handle id is kInvalidServiceWorkerHandleId, returns null instead.
   static scoped_ptr<ServiceWorkerHandleReference> Adopt(
       const ServiceWorkerObjectInfo& info,
       ThreadSafeSender* sender);
 
   ~ServiceWorkerHandleReference();
 
   const ServiceWorkerObjectInfo& info() const { return info_; }
   int handle_id() const { return info_.handle_id; }
   const GURL& url() const { return info_.url; }
   blink::WebServiceWorkerState state() const { return info_.state; }
   void set_state(blink::WebServiceWorkerState state) { info_.state = state; }
   int64 version_id() const { return info_.version_id; }
 
  private:
   ServiceWorkerHandleReference(const ServiceWorkerObjectInfo& info,
                                ThreadSafeSender* sender,
                                bool increment_ref_in_ctor);
   ServiceWorkerObjectInfo info_;
   scoped_refptr<ThreadSafeSender> sender_;
   DISALLOW_COPY_AND_ASSIGN(ServiceWorkerHandleReference);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_CHILD_SERVICE_WORKER_SERVICE_WORKER_HANDLE_REFERENCE_H_