Add FilePath to base namespace.

chrome/browser/safe_browsing/signature_util.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.
 //
 // Utility functions to check executable signatures for malicious binary
 // detection.  Each platform has its own implementation of this class.
 
 #ifndef CHROME_BROWSER_SAFE_BROWSING_SIGNATURE_UTIL_H_
 #define CHROME_BROWSER_SAFE_BROWSING_SIGNATURE_UTIL_H_
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 
+namespace base {
 class FilePath;
+}
 
 namespace safe_browsing {
 class ClientDownloadRequest_SignatureInfo;
 
 class SignatureUtil : public base::RefCountedThreadSafe<SignatureUtil> {
  public:
   SignatureUtil();
 
   // Fills in the DownloadRequest_SignatureInfo for the given file path.
   // This method may be called on any thread.
   virtual void CheckSignature(
-      const FilePath& file_path,
+      const base::FilePath& file_path,
       ClientDownloadRequest_SignatureInfo* signature_info);
 
  protected:
   friend class base::RefCountedThreadSafe<SignatureUtil>;
   virtual ~SignatureUtil();
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SignatureUtil);
 };
 }  // namespace safe_browsing
 
 #endif  // CHROME_BROWSER_SAFE_BROWSING_SIGNATURE_UTIL_H_