Work around CancelableCompletionCallback threading restrictions.

webkit/appcache/appcache_quota_client.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 WEBKIT_APPCACHE_APPCACHE_QUOTA_CLIENT_H_
 #define WEBKIT_APPCACHE_APPCACHE_QUOTA_CLIENT_H_
 
 #include <deque>
 #include <map>
 #include <string>
@@ skipping 47 matching lines @@
 
   APPCACHE_EXPORT explicit AppCacheQuotaClient(AppCacheService* service);
 
   void DidDeleteAppCachesForOrigin(int rv);
   void GetOriginsHelper(quota::StorageType type,
                         const std::string& opt_host,
                         const GetOriginsCallback& callback);
   void ProcessPendingRequests();
   void DeletePendingRequests();
   const AppCacheStorage::UsageMap* GetUsageMap();
+  net::CancelableCompletionCallback* GetServiceDeleteCallback();
 
   // For use by appcache internals during initialization and shutdown.
   APPCACHE_EXPORT void NotifyAppCacheReady();
   APPCACHE_EXPORT void NotifyAppCacheDestroyed();
 
   // Prior to appcache service being ready, we have to queue
   // up reqeusts and defer acting on them until we're ready.
   RequestQueue pending_batch_requests_;
   RequestQueue pending_serial_requests_;
 
   // And once it's ready, we can only handle one delete request at a time,
   // so we queue up additional requests while one is in already in progress.
   DeletionCallback current_delete_request_callback_;
-  net::CancelableCompletionCallback service_delete_callback_;
+  scoped_ptr<net::CancelableCompletionCallback> service_delete_callback_;

[mnaganov (inactive), 2012/02/27 22:02:10]

Perhaps, mention that it is lazily created, or maybe reflect this in the name.

[mnaganov (inactive), 2012/02/27 22:02:10]

Does it play well regarding to destruction? WeakPtrFactory checks the thread in
the destructor, and CancellableCallback owns one. I'm not sure if we are really
running destructors at exit, but I think it's worth checking.

[michaeln, 2012/02/27 22:54:15]

Aside from construction, this class is used deleted on the IO thread.

 
   AppCacheService* service_;
   bool appcache_is_ready_;
   bool quota_manager_is_destroyed_;
 
   DISALLOW_COPY_AND_ASSIGN(AppCacheQuotaClient);
 };
 
 }  // namespace appcache
 
 #endif  // WEBKIT_APPCACHE_APPCACHE_QUOTA_CLIENT_H_