chrome: Cleanup class/struct forward declarations

chrome/browser/media_galleries/fileapi/mtp_file_stream_reader.h

 // Copyright 2014 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_BROWSER_MEDIA_GALLERIES_FILEAPI_MTP_FILE_STREAM_READER_H_
 #define CHROME_BROWSER_MEDIA_GALLERIES_FILEAPI_MTP_FILE_STREAM_READER_H_
 
 #include <stdint.h>
 
 #include "base/bind.h"
 #include "base/files/file.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "storage/browser/fileapi/file_stream_reader.h"
 #include "storage/browser/fileapi/file_system_url.h"
 #include "storage/browser/storage_browser_export.h"
 
-namespace base {
-class FilePath;
-}
-
 namespace storage {
 class FileSystemContext;
 }
 
 class MTPFileStreamReader
     : public NON_EXPORTED_BASE(storage::FileStreamReader) {
  public:
   MTPFileStreamReader(storage::FileSystemContext* file_system_context,
                       const storage::FileSystemURL& url,
                       int64_t initial_offset,
@@ skipping 28 matching lines @@
   const base::Time expected_modification_time_;
 
   bool media_header_validated_;
 
   base::WeakPtrFactory<MTPFileStreamReader> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MTPFileStreamReader);
 };
 
 #endif  // CHROME_BROWSER_MEDIA_GALLERIES_FILEAPI_MTP_FILE_STREAM_READER_H_