src/: Update the remaining include paths of string_split.h to its new location.

net/base/host_port_pair.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 "net/base/host_port_pair.h"
 
 #include "base/string_number_conversions.h"
-#include "base/string_split.h"
 #include "base/string_util.h"
 #include "base/stringprintf.h"
+#include "base/strings/string_split.h"
 #include "googleurl/src/gurl.h"
 #include "net/base/ip_endpoint.h"
 
 namespace net {
 
 HostPortPair::HostPortPair() : port_(0) {}
 HostPortPair::HostPortPair(const std::string& in_host, uint16 in_port)
     : host_(in_host), port_(in_port) {}
 
 // static
@@ skipping 29 matching lines @@
   // Check to see if the host is an IPv6 address.  If so, added brackets.
   if (host_.find(':') != std::string::npos) {
     DCHECK_NE(host_[0], '[');
     return base::StringPrintf("[%s]", host_.c_str());
   }
 
   return host_;
 }
 
 }  // namespace net