AppCaches which belong to hosted apps are not protected from deletion

content/browser/appcache/chrome_appcache_service.h

 // Copyright (c) 2011 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_APPCACHE_CHROME_APPCACHE_SERVICE_H_
 #define CONTENT_BROWSER_APPCACHE_CHROME_APPCACHE_SERVICE_H_
 #pragma once
 
 #include "base/memory/ref_counted.h"
+#include "base/synchronization/waitable_event.h"
 #include "content/browser/browser_thread.h"
 #include "content/common/notification_observer.h"
 #include "content/common/notification_registrar.h"
+#include "net/base/completion_callback.h"
 #include "webkit/appcache/appcache_policy.h"
 #include "webkit/appcache/appcache_service.h"
 #include "webkit/quota/special_storage_policy.h"
 
 class FilePath;
 
+namespace appcache {
+class TestableChromeAppCacheService;
+}
+
 namespace content {
 class ResourceContext;
 }
 
 // An AppCacheService subclass used by the chrome. There is an instance
 // associated with each Profile. This derivation adds refcounting semantics
 // since a profile has multiple URLRequestContexts which refer to the same
 // object, and those URLRequestContexts are refcounted independently of the
 // owning profile.
 //
 // All methods, except the ctor, are expected to be called on
 // the IO thread (unless specifically called out in doc comments).
 class ChromeAppCacheService
     : public base::RefCountedThreadSafe<ChromeAppCacheService,
                                         BrowserThread::DeleteOnIOThread>,
       public appcache::AppCacheService,
       public appcache::AppCachePolicy,
       public NotificationObserver {
  public:
   explicit ChromeAppCacheService(quota::QuotaManagerProxy* proxy);
 
   void InitializeOnIOThread(
       const FilePath& cache_path,  // may be empty to use in-memory structures
       const content::ResourceContext* resource_context,
-      scoped_refptr<quota::SpecialStoragePolicy> special_storage_policy,
-      bool clear_local_state_on_exit);
+      scoped_refptr<quota::SpecialStoragePolicy> special_storage_policy);
 
-  void SetClearLocalStateOnExit(bool clear_local_state);
+  // Safe to call from any thread
+  base::WaitableEvent* ClearAppCache(net::CompletionCallback* callback);
 
  private:
   friend class BrowserThread;
   friend class DeleteTask<ChromeAppCacheService>;
+  // TestableChromeAppService is a subclass of ChromeAppCacheService used in the
+  // unit tests
+  friend class appcache::TestableChromeAppCacheService;
+  FRIEND_TEST_ALL_PREFIXES(BrowsingDataRemoverTest, RemoveAppCacheForever);
 
   virtual ~ChromeAppCacheService();
 
   // AppCachePolicy overrides
   virtual bool CanLoadAppCache(const GURL& manifest_url);
   virtual int CanCreateAppCache(const GURL& manifest_url,
                                 net::CompletionCallback* callback);
 
   // NotificationObserver override
   virtual void Observe(int type,
                        const NotificationSource& source,
                        const NotificationDetails& details);
 
+  // Appcache clearing helpers and callbacks
+  void OnGotAppCacheInfo(int rv);
+  void OnOriginDeleted(int rv);
+  void OnClearedAppCache();
+
   const content::ResourceContext* resource_context_;
   NotificationRegistrar registrar_;
-  bool clear_local_state_on_exit_;
   FilePath cache_path_;
+  net::CompletionCallbackImpl<ChromeAppCacheService>
+      appcache_got_info_callback_;
+  net::CompletionCallbackImpl<ChromeAppCacheService>
+      origin_deleted_callback_;
+  scoped_refptr<appcache::AppCacheInfoCollection> appcache_info_;
+  int origins_to_be_deleted_count_;
+  scoped_ptr<base::WaitableEvent> appcaches_cleared_event_;
+  net::CompletionCallback* appcaches_cleared_callback_;
+  bool waiting_for_clear_appcaches_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeAppCacheService);
 };
 
 #endif  // CONTENT_BROWSER_APPCACHE_CHROME_APPCACHE_SERVICE_H_