Use a direct include of strings headers in chrome_frame/.

chrome_frame/test/policy_settings_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 "base/at_exit.h"
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/stringprintf.h"
+#include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/win/registry.h"
 #include "chrome_frame/policy_settings.h"
 #include "chrome_frame/test/chrome_frame_test_utils.h"
 #include "content/public/common/content_switches.h"
 #include "policy/policy_constants.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using base::win::RegKey;
 using chrome_frame_test::ScopedVirtualizeHklmAndHkcu;
@@ skipping 219 matching lines @@
 
     base::FilePath program_path(FILE_PATH_LITERAL("my_chrome.exe"));
     CommandLine new_cmd_line(program_path);
     new_cmd_line.AppendArguments(additional_params, false);
     EXPECT_NE(new_cmd_line.GetProgram(), additional_params.GetProgram());
     EXPECT_TRUE(new_cmd_line.HasSwitch(switches::kDisableWebKitMediaSource));
 
     DeleteChromeFramePolicyEntries(root[i]);
   }
 }