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

net/http/http_stream_factory.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/http/http_stream_factory.h"
 
 #include "base/logging.h"
 #include "base/string_number_conversions.h"
-#include "base/string_split.h"
+#include "base/strings/string_split.h"
 #include "googleurl/src/gurl.h"
 #include "net/base/host_mapping_rules.h"
 #include "net/base/host_port_pair.h"
 
 namespace net {
 
 // WARNING: If you modify or add any static flags, you must keep them in sync
 // with |ResetStaticSettingsToInit|. This is critical for unit test isolation.
 
 // static
@@ skipping 184 matching lines @@
       enabled_protocols_[QUIC_1] = true;
     }
   }
   // TODO(rch): Remove all support for spdy/1.
   enabled_protocols_[NPN_SPDY_1] = false;
 }
 
 HttpStreamFactory::HttpStreamFactory() {}
 
 }  // namespace net