Convert JsonWriter::Write to taking a const ref for the in-param

chrome/test/chromedriver/performance_logger.cc

 // Copyright 2014 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 "chrome/test/chromedriver/performance_logger.h"
 
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 105 matching lines @@
 void PerformanceLogger::AddLogEntry(
     Log::Level level,
     const std::string& webview,
     const std::string& method,
     const base::DictionaryValue& params) {
   base::DictionaryValue log_message_dict;
   log_message_dict.SetString("webview", webview);
   log_message_dict.SetString("message.method", method);
   log_message_dict.Set("message.params", params.DeepCopy());
   std::string log_message_json;
-  base::JSONWriter::Write(&log_message_dict, &log_message_json);
+  base::JSONWriter::Write(log_message_dict, &log_message_json);
 
   // TODO(klm): extract timestamp from params?
   // Look at where it is for Page, Network, Timeline, and trace events.
   log_->AddEntry(level, log_message_json);
 }
 
 void PerformanceLogger::AddLogEntry(
     const std::string& webview,
     const std::string& method,
     const base::DictionaryValue& params) {
@@ skipping 142 matching lines @@
   if (status.IsError())
     return status;
 
   return StartTrace();
 }
 
 Status PerformanceLogger::IsTraceDone(bool* trace_done) const {
   *trace_done = !trace_buffering_;
   return Status(kOk);
 }