Use a direct include of strings headers in url/, win8/.

url/url_util_internal.h

 // Copyright 2013 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.
 
 #ifndef URL_URL_UTIL_INTERNAL_H_
 #define URL_URL_UTIL_INTERNAL_H_
 
 #include <string>
 
-#include "base/string16.h"
+#include "base/strings/string16.h"
 #include "url/url_parse.h"
 
 namespace url_util {
 
 extern const char kFileScheme[];
 extern const char kFileSystemScheme[];
 extern const char kMailtoScheme[];
 
 // Given a string and a range inside the string, compares it to the given
 // lower-case |compare_to| buffer.
 bool CompareSchemeComponent(const char* spec,
                             const url_parse::Component& component,
                             const char* compare_to);
 bool CompareSchemeComponent(const char16* spec,
                             const url_parse::Component& component,
                             const char* compare_to);
 
 }  // namespace url_util
 
 #endif  // URL_URL_UTIL_INTERNAL_H_