Replace use of logging::DEBUG_MODE with DCHECK_IS_ON().

components/sync/engine_impl/traffic_logger.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 "components/sync/engine_impl/traffic_logger.h"
 
 #include <memory>
 #include <string>
 
 #include "base/json/json_writer.h"
 #include "base/logging.h"
 #include "base/values.h"
 #include "components/sync/protocol/proto_value_conversions.h"
 #include "components/sync/protocol/sync.pb.h"
 
 namespace syncer {
 
 namespace {
 template <class T>
 void LogData(const T& data,
              std::unique_ptr<base::DictionaryValue> (
                  *to_dictionary_value)(const T&, bool),
              const std::string& description) {
-  if (::logging::DEBUG_MODE && VLOG_IS_ON(1)) {
+  if (DCHECK_IS_ON() && VLOG_IS_ON(1)) {
     std::unique_ptr<base::DictionaryValue> value =
         (*to_dictionary_value)(data, true /* include_specifics */);
     std::string message;
     base::JSONWriter::WriteWithOptions(
         *value, base::JSONWriter::OPTIONS_PRETTY_PRINT, &message);
     DVLOG(1) << "\n" << description << "\n" << message << "\n";
   }
 }
 }  // namespace
 
 void LogClientToServerMessage(const sync_pb::ClientToServerMessage& msg) {
   LogData(msg, &ClientToServerMessageToValue,
           "******Client To Server Message******");
 }
 
 void LogClientToServerResponse(
     const sync_pb::ClientToServerResponse& response) {
   LogData(response, &ClientToServerResponseToValue,
           "******Server Response******");
 }
 
 }  // namespace syncer