Service Worker: in Unregister, wait until after the active worker no longer controls a document

content/browser/service_worker/service_worker_registration.h

 // Copyright 2013 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_REGISTRATION_H_
 #define CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_REGISTRATION_H_
 
 #include "base/basictypes.h"
 #include "base/gtest_prod_util.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "content/browser/service_worker/service_worker_version.h"
 #include "content/common/content_export.h"
 #include "content/common/service_worker/service_worker_types.h"
 #include "url/gurl.h"
 
 namespace content {
 
 class ServiceWorkerRegistrationInfo;
 class ServiceWorkerVersion;
 
 // This class represents a service worker registration. The
 // scope and script url are constant for the life of the persistent
 // registration. It's refcounted to facillitate multiple controllees
 // being associated with the same registration. The class roughly
 // corresponds to navigator.serviceWorker.registgration.
 class CONTENT_EXPORT ServiceWorkerRegistration
-    : NON_EXPORTED_BASE(public base::RefCounted<ServiceWorkerRegistration>) {
+    : NON_EXPORTED_BASE(public base::RefCounted<ServiceWorkerRegistration>),
+      public ServiceWorkerVersion::Listener {
  public:
   typedef base::Callback<void(ServiceWorkerStatusCode status)> StatusCallback;
 
   class Listener {
    public:
     virtual void OnVersionAttributesChanged(
         ServiceWorkerRegistration* registration,
         ChangedVersionAttributesMask changed_mask,
         const ServiceWorkerRegistrationInfo& info)  = 0;
   };
@@ skipping 12 matching lines @@
   }
 
   ServiceWorkerVersion* waiting_version() const {
     return waiting_version_.get();
   }
 
   ServiceWorkerVersion* installing_version() const {
     return installing_version_.get();
   }
 
+  bool is_uninstalling() const { return is_uninstalling_; }
+
   void AddListener(Listener* listener);
   void RemoveListener(Listener* listener);
 
   ServiceWorkerRegistrationInfo GetInfo();
 
   // Sets the corresposding version attribute and resets the position
   // (if any) left vacant (ie. by a waiting version being promoted).
   // Also notifies listeners via OnVersionAttributesChanged.
   void SetActiveVersion(ServiceWorkerVersion* version);
   void SetWaitingVersion(ServiceWorkerVersion* version);
   void SetInstallingVersion(ServiceWorkerVersion* version);
 
   // If version is the installing, waiting, active version of this
   // registation, the method will reset that field to NULL, and notify
   // listeners via OnVersionAttributesChanged.
   void UnsetVersion(ServiceWorkerVersion* version);
 
+  virtual void OnNoControllees(ServiceWorkerVersion* version) OVERRIDE;
+
   // This method corresponds to the [[Activate]] algorithm described in
   // the service worker specification. It's only valid to call this method
   // when the registration's active version has no controllees.
   void ActivateWaitingVersion(const StatusCallback& completion_callback);
 
+  // Triggers the [[ClearRegistration]] algorithm when the currently
+  // active version has no controllees. Deletes this registration
+  // from storage immediately.
+  void ClearWhenReady();
+
+  // Restores this registration in storage and cancels the pending
+  // [[ClearRegistration]] algorithm. If the algorithm was already triggered,
+  // does nothing.
+  void AbortPendingClear();
+
  private:
-  ~ServiceWorkerRegistration();
+  virtual ~ServiceWorkerRegistration();
+  void Clear();
   friend class base::RefCounted<ServiceWorkerRegistration>;
 
   void SetVersionInternal(
       ServiceWorkerVersion* version,
       scoped_refptr<ServiceWorkerVersion>* data_member,
       int change_flag);
   void UnsetVersionInternal(
       ServiceWorkerVersion* version,
       ChangedVersionAttributesMask* mask);
   void OnActivateEventFinished(
       ServiceWorkerVersion* activating_version,
       const StatusCallback& completion_callback,
       ServiceWorkerStatusCode status);
 
   const GURL pattern_;
   const GURL script_url_;
   const int64 registration_id_;
+  bool is_uninstalling_;
   scoped_refptr<ServiceWorkerVersion> active_version_;
   scoped_refptr<ServiceWorkerVersion> waiting_version_;
   scoped_refptr<ServiceWorkerVersion> installing_version_;
   ObserverList<Listener> listeners_;
   base::WeakPtr<ServiceWorkerContextCore> context_;
 
   DISALLOW_COPY_AND_ASSIGN(ServiceWorkerRegistration);
 };
+
 }  // namespace content
+
 #endif  // CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_REGISTRATION_H_