Use a direct include of strings headers in chrome/installer/, part 2.

chrome/installer/util/installer_state_unittest.cc

 // 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.
 
 #include <windows.h>
 
 #include <fstream>
 
 #include "base/base_paths.h"
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/files/file_enumerator.h"
 #include "base/files/file_path.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/path_service.h"
 #include "base/process_util.h"
-#include "base/string_util.h"
+#include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/test/test_reg_util_win.h"
 #include "base/version.h"
 #include "base/win/registry.h"
 #include "base/win/scoped_handle.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/installer/test/alternate_version_generator.h"
 #include "chrome/installer/util/fake_installation_state.h"
 #include "chrome/installer/util/fake_product_state.h"
 #include "chrome/installer/util/google_update_constants.h"
@@ skipping 721 matching lines @@
   // Critical update newer than the new version.
   EXPECT_FALSE(
       installer_state.DetermineCriticalVersion(NULL, *pv_version_).IsValid());
   EXPECT_FALSE(
       installer_state.DetermineCriticalVersion(opv_version_, *pv_version_)
           .IsValid());
   EXPECT_FALSE(
       installer_state.DetermineCriticalVersion(pv_version_, *pv_version_)
           .IsValid());
 }