Avoid sync IPCs for FileSystem API

chrome/renderer/worker_permission_client_proxy.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 CHROME_RENDERER_WORKER_PERMISSION_CLIENT_PROXY_H_
 #define CHROME_RENDERER_WORKER_PERMISSION_CLIENT_PROXY_H_
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "third_party/WebKit/public/web/WebWorkerPermissionClientProxy.h"
@@ skipping 18 matching lines @@
  public:
   WorkerPermissionClientProxy(content::RenderFrame* render_frame,
                               blink::WebFrame* frame);
   virtual ~WorkerPermissionClientProxy();
 
   // WebWorkerPermissionClientProxy overrides.
   virtual bool allowDatabase(const blink::WebString& name,
                              const blink::WebString& display_name,
                              unsigned long estimated_size);
   virtual bool allowFileSystem();
+  virtual void requestFileSystemAccess(
+      const blink::WebPermissionCallbacks& callbacks);
   virtual bool allowIndexedDB(const blink::WebString& name);
 
  private:
   // Loading document context for this worker.
   const int routing_id_;
   bool is_unique_origin_;
   GURL document_origin_url_;
   GURL top_frame_origin_url_;
   scoped_refptr<IPC::SyncMessageFilter> sync_message_filter_;
 
   DISALLOW_COPY_AND_ASSIGN(WorkerPermissionClientProxy);
 };
 
 #endif  // CHROME_RENDERER_WORKER_PERMISSION_CLIENT_PROXY_H_