Cleanup: Remove using statements from webkit/fileapi header files.

webkit/fileapi/media/mtp_device_delegate.h

 // Copyright (c) 2012 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_MEDIA_MTP_DEVICE_DELEGATE_H_
 #define WEBKIT_FILEAPI_MEDIA_MTP_DEVICE_DELEGATE_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "base/platform_file.h"
 #include "webkit/fileapi/file_system_file_util.h"
@@ skipping 22 matching lines @@
   // the file entries of |root| path. The instance needs to be freed by the
   // caller, and its lifetime should not extend past when the current call
   // returns to the main media task runner thread.
   virtual scoped_ptr<FileSystemFileUtil::AbstractFileEnumerator>
       CreateFileEnumerator(const FilePath& root,
                            bool recursive) = 0;
 
   // Updates the temporary snapshot file contents given by |local_path| with
   // media file contents given by |device_file_path| and also returns the
   // metadata of the temporary file.
-  virtual PlatformFileError CreateSnapshotFile(
+  virtual base::PlatformFileError CreateSnapshotFile(
       const FilePath& device_file_path,
       const FilePath& local_path,
       base::PlatformFileInfo* file_info) = 0;
 
   // Called when the
   // (1) Browser application is in shutdown mode (or)
   // (2) Last extension using this MTP device is destroyed (or)
   // (3) Attached MTP device is removed (or)
   // (4) User revoked the MTP device gallery permission.
   // Ownership of |MTPDeviceDelegate| is handed off to the delegate
   // implementation class by this call. This function should take care of
   // deleting itself on the right thread. This function should cancel all the
   // pending requests before posting any message to delete itself.
   // Called on the UI thread.
   virtual void CancelPendingTasksAndDeleteDelegate() = 0;
 
  protected:
   // Always destruct this object via CancelPendingTasksAndDeleteDelegate().
   virtual ~MTPDeviceDelegate() {}
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_FILEAPI_MEDIA_MTP_DEVICE_DELEGATE_H_