Add 1st cut of FileSystemUsageTracker that tracks the usage changes in FileSystem API.

webkit/fileapi/sandboxed_file_system_context.h

 // Copyright (c) 2010 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_FILEAPI_SANDBOXED_FILE_SYSTEM_CONTEXT_H_
 #define WEBKIT_FILEAPI_SANDBOXED_FILE_SYSTEM_CONTEXT_H_
 
 #include "base/ref_counted.h"
 #include "base/scoped_ptr.h"
 
 class FilePath;
 class GURL;
 
 namespace base {
 class MessageLoopProxy;
 }
 
 namespace fileapi {
 
 class FileSystemPathManager;
 class FileSystemQuotaManager;
+class FileSystemUsageTracker;
 class SandboxedFileSystemContext;
 
 struct DefaultContextDeleter;
 
 // This class keeps and provides a sandboxed file system context.
 class SandboxedFileSystemContext
     : public base::RefCountedThreadSafe<SandboxedFileSystemContext,
                                         DefaultContextDeleter> {
  public:
   SandboxedFileSystemContext(
       scoped_refptr<base::MessageLoopProxy> file_message_loop,
       scoped_refptr<base::MessageLoopProxy> io_message_loop,
       const FilePath& profile_path,
       bool is_incognito,
       bool allow_file_access_from_files,
       bool unlimited_quota);
   ~SandboxedFileSystemContext();
 
   void Shutdown();
 
   void DeleteDataForOriginOnFileThread(const GURL& origin_url);
 
   // Quota related methods.
   void SetOriginQuotaUnlimited(const GURL& url);
   void ResetOriginQuotaUnlimited(const GURL& url);
 
   FileSystemPathManager* path_manager() { return path_manager_.get(); }
   FileSystemQuotaManager* quota_manager() { return quota_manager_.get(); }
+  FileSystemUsageTracker* usage_tracker() { return usage_tracker_.get(); }
 
  private:
   friend struct DefaultContextDeleter;
   void DeleteOnCorrectThread() const;
 
-  bool allow_file_access_from_files_;
   scoped_refptr<base::MessageLoopProxy> file_message_loop_;
   scoped_refptr<base::MessageLoopProxy> io_message_loop_;
   scoped_ptr<FileSystemPathManager> path_manager_;
   scoped_ptr<FileSystemQuotaManager> quota_manager_;
+  scoped_ptr<FileSystemUsageTracker> usage_tracker_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(SandboxedFileSystemContext);
 };
 
 struct DefaultContextDeleter {
   static void Destruct(const SandboxedFileSystemContext* context) {
     context->DeleteOnCorrectThread();
   }
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_FILEAPI_SANDBOXED_FILE_SYSTEM_CONTEXT_H_