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

url/url_canon_ip.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_CANON_IP_H_
 #define URL_URL_CANON_IP_H_
 
-#include "base/string16.h"
+#include "base/strings/string16.h"
 #include "url/url_canon.h"
 #include "url/url_export.h"
 #include "url/url_parse.h"
 
 namespace url_canon {
 
 // Writes the given IPv4 address to |output|.
 URL_EXPORT void AppendIPv4Address(const unsigned char address[4],
                                   CanonOutput* output);
 
@@ skipping 56 matching lines @@
 URL_EXPORT bool IPv6AddressToNumber(const char* spec,
                                     const url_parse::Component& host,
                                     unsigned char address[16]);
 URL_EXPORT bool IPv6AddressToNumber(const char16* spec,
                                     const url_parse::Component& host,
                                     unsigned char address[16]);
 
 }  // namespace url_canon
 
 #endif  // URL_URL_CANON_IP_H_