Make Platform::queryStorageUsageAndQuota work from worker threads

content/child/quota_dispatcher.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_CHILD_QUOTA_DISPATCHER_H_
 #define CONTENT_CHILD_QUOTA_DISPATCHER_H_
 
 #include <map>
 #include <set>
 
 #include "base/basictypes.h"
 #include "base/id_map.h"
-#include "ipc/ipc_listener.h"
+#include "base/memory/ref_counted.h"
+#include "webkit/child/worker_task_runner.h"
 #include "webkit/common/quota/quota_types.h"
 
 class GURL;
 
 namespace IPC {
 class Message;
 }
 
 namespace WebKit {
 class WebStorageQuotaCallbacks;
 }
 
 namespace content {
 
+class ThreadSafeSender;
+
 // Dispatches and sends quota related messages sent to/from a child
 // process from/to the main browser process.  There is one instance
-// per child process.  Messages are dispatched on the main child thread.
-class QuotaDispatcher : public IPC::Listener {
+// per each thread.  Thread-specific instance can be obtained by
+// ThreadSpecificInstance().
+class QuotaDispatcher : public webkit_glue::WorkerTaskRunner::Observer {
  public:
   class Callback {
    public:
     virtual ~Callback() {}
     virtual void DidQueryStorageUsageAndQuota(int64 usage, int64 quota) = 0;
     virtual void DidGrantStorageQuota(int64 granted_quota) = 0;
     virtual void DidFail(quota::QuotaStatusCode status) = 0;
   };
 
-  QuotaDispatcher();
+  explicit QuotaDispatcher(ThreadSafeSender* thread_safe_sender);
   virtual ~QuotaDispatcher();
 
-  // IPC::Listener implementation.
-  virtual bool OnMessageReceived(const IPC::Message& msg) OVERRIDE;
+  // |thread_safe_sender| is used if calling this leads to construction.
+  static QuotaDispatcher* ThreadSpecificInstance(
+      ThreadSafeSender* thread_safe_sender);
+
+  // webkit_glue::WorkerTaskRunner::Observer implementation.
+  virtual void OnWorkerRunLoopStopped() OVERRIDE;
+
+  void OnMessageReceived(const IPC::Message& msg);
 
   void QueryStorageUsageAndQuota(const GURL& gurl,
                                  quota::StorageType type,
                                  Callback* callback);
   void RequestStorageQuota(int render_view_id,
                            const GURL& gurl,
                            quota::StorageType type,
                            int64 requested_size,
                            Callback* callback);
 
   // Creates a new Callback instance for WebStorageQuotaCallbacks.
   static Callback* CreateWebStorageQuotaCallbacksWrapper(
       WebKit::WebStorageQuotaCallbacks* callbacks);
 
  private:
   // Message handlers.
-  void DidQueryStorageUsageAndQuota(int request_id,
+  void DidQueryStorageUsageAndQuota(int ipc_thread_id,
+                                    int request_id,
                                     int64 current_usage,
                                     int64 current_quota);
-  void DidGrantStorageQuota(int request_id,
+  void DidGrantStorageQuota(int ipc_thread_id,
+                            int request_id,
                             int64 granted_quota);
-  void DidFail(int request_id, quota::QuotaStatusCode error);
+  void DidFail(int ipc_thread_id,
+               int request_id,
+               quota::QuotaStatusCode error);
 
   IDMap<Callback, IDMapOwnPointer> pending_quota_callbacks_;
 
+  scoped_refptr<ThreadSafeSender> thread_safe_sender_;
+
   DISALLOW_COPY_AND_ASSIGN(QuotaDispatcher);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_CHILD_QUOTA_DISPATCHER_H_