chrome: Cleanup class/struct forward declarations

chrome/installer/test/alternate_version_generator.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.
 //
 // This file exposes the public interface to the mini_installer re-versioner.
 
 #ifndef CHROME_INSTALLER_TEST_ALTERNATE_VERSION_GENERATOR_H_
 #define CHROME_INSTALLER_TEST_ALTERNATE_VERSION_GENERATOR_H_
 
 #include "base/strings/string16.h"
 
 namespace base {
 class FilePath;
-class Version;
 }
 
 namespace upgrade_test {
 
 enum Direction {
   PREVIOUS_VERSION,
   NEXT_VERSION
 };
 
 // Generates an alternate mini_installer.exe using the one indicated by
@@ skipping 14 matching lines @@
 // version of the generated file. Otherwise, returns an empty string. Note that
 // |target_file| may still be mutated on failure.
 base::string16 GenerateAlternatePEFileVersion(
     const base::FilePath& original_file,
     const base::FilePath& target_file,
     Direction direction);
 
 }  // namespace upgrade_test
 
 #endif  // CHROME_INSTALLER_TEST_ALTERNATE_VERSION_GENERATOR_H_