Revert of base: Remove using:: declaration from version.h header.

chrome/installer/setup/setup_util.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.
 //
 // This file declares util functions for setup project. It also declares a
 // few functions that the Chrome component updater uses for patching binary
 // deltas.
 
 #ifndef CHROME_INSTALLER_SETUP_SETUP_UTIL_H_
 #define CHROME_INSTALLER_SETUP_SETUP_UTIL_H_
@@ skipping 31 matching lines @@
 // Courgette's flavor of bsdiff. Returns 0 in case of success, or
 // kBsdiffErrorOffset + a bsdiff status code in case of errors.
 // See courgette/third_party/bsdiff.h for details.
 int BsdiffPatchFiles(const base::FilePath& src,
                      const base::FilePath& patch,
                      const base::FilePath& dest);
 
 // Find the version of Chrome from an install source directory.
 // Chrome_path should contain at least one version folder.
 // Returns the maximum version found or NULL if no version is found.
-base::Version* GetMaxVersionFromArchiveDir(const base::FilePath& chrome_path);
+Version* GetMaxVersionFromArchiveDir(const base::FilePath& chrome_path);
 
 // Returns the uncompressed archive of the installed version that serves as the
 // source for patching.  If |desired_version| is valid, only the path to that
 // version will be returned, or empty if it doesn't exist.
 base::FilePath FindArchiveToPatch(const InstallationState& original_state,
                                   const InstallerState& installer_state,
                                   const base::Version& desired_version);
 
 // Spawns a new process that waits for a specified amount of time before
 // attempting to delete |path|.  This is useful for setup to delete the
@@ skipping 86 matching lines @@
   // The previous state of the privilege this object is responsible for. As set
   // by AdjustTokenPrivileges() upon construction.
   TOKEN_PRIVILEGES previous_privileges_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(ScopedTokenPrivilege);
 };
 
 }  // namespace installer
 
 #endif  // CHROME_INSTALLER_SETUP_SETUP_UTIL_H_