Use a direct include of strings headers in chromeos/.

chromeos/network/onc/onc_utils.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 "chromeos/network/onc/onc_utils.h"
 
 #include "base/base64.h"
 #include "base/json/json_reader.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
-#include "base/string_util.h"
+#include "base/strings/string_util.h"
 #include "base/values.h"
 #include "chromeos/network/network_event_log.h"
 #include "chromeos/network/onc/onc_mapper.h"
 #include "chromeos/network/onc/onc_signature.h"
 #include "chromeos/network/onc/onc_utils.h"
 #include "chromeos/network/onc/onc_validator.h"
 #include "crypto/encryptor.h"
 #include "crypto/hmac.h"
 #include "crypto/symmetric_key.h"
 
@@ skipping 321 matching lines @@
   if (toplevel_onc->GetListWithoutPathExpansion(
           onc::toplevel_config::kNetworkConfigurations, &validated_networks)) {
     network_configs->Swap(validated_networks);
   }
 
   return success;
 }
 
 }  // namespace onc
 }  // namespace chromeos