Add FilePath to base namespace.

chrome/browser/nacl_host/pnacl_file_host.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 CHROME_BROWSER_NACL_HOST_PNACL_FILE_HOST_H_
 #define CHROME_BROWSER_NACL_HOST_PNACL_FILE_HOST_H_
 
 #include <string>
 
 class ChromeRenderMessageFilter;
+
+namespace base {
 class FilePath;
+}
 
 namespace IPC {
 class Message;
 }  // namespace IPC
 
 // Opens Pnacl Files in the Browser process, on behalf of the NaCl plugin.
 
 namespace pnacl_file_host {
 
 // Open a Pnacl file (readonly) on behalf of the NaCl plugin.
 void GetReadonlyPnaclFd(ChromeRenderMessageFilter* chrome_render_message_filter,
                         const std::string& filename,
                         IPC::Message* reply_msg);
 
 // Return true if the filename requested is valid for opening.
-// Sets file_to_open to the FilePath which we will attempt to open.
+// Sets file_to_open to the base::FilePath which we will attempt to open.
 bool PnaclCanOpenFile(const std::string& filename,
-                      FilePath* file_to_open);
+                      base::FilePath* file_to_open);
 
 // Creates a temporary file that will be deleted when the last handle
 // is closed, or earlier.
 void CreateTemporaryFile(
     ChromeRenderMessageFilter* chrome_render_message_filter,
     IPC::Message* reply_msg);
 
 }  // namespace pnacl_file_host
 
 #endif  // CHROME_BROWSER_NACL_HOST_PNACL_FILE_HOST_H_