Cleanup: Remove unneeded forward declarations in webkit/.

webkit/fileapi/file_system_context.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_FILEAPI_FILE_SYSTEM_CONTEXT_H_
 #define WEBKIT_FILEAPI_FILE_SYSTEM_CONTEXT_H_
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "webkit/fileapi/file_system_types.h"
 #include "webkit/quota/special_storage_policy.h"
 
 class FilePath;
 class GURL;
 
 namespace base {
 class MessageLoopProxy;
 }
 
 namespace quota {
-class QuotaClient;
 class QuotaManagerProxy;
 }
 
 namespace fileapi {
 
 class FileSystemContext;
 class FileSystemPathManager;
 class FileSystemQuotaUtil;
-class FileSystemUsageTracker;
 class SandboxMountPointProvider;
 
 struct DefaultContextDeleter;
 
 // This class keeps and provides a file system context for FileSystem API.
 class FileSystemContext
     : public base::RefCountedThreadSafe<FileSystemContext,
                                         DefaultContextDeleter> {
  public:
   FileSystemContext(
@@ skipping 39 matching lines @@
 
 struct DefaultContextDeleter {
   static void Destruct(const FileSystemContext* context) {
     context->DeleteOnCorrectThread();
   }
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_FILEAPI_FILE_SYSTEM_CONTEXT_H_