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

sync/internal_api/public/engine/model_safe_worker.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 "sync/internal_api/public/engine/model_safe_worker.h"
 
 #include "base/bind.h"
 #include "base/json/json_writer.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/values.h"
 
 namespace syncer {
 
 scoped_ptr<base::DictionaryValue> ModelSafeRoutingInfoToValue(
     const ModelSafeRoutingInfo& routing_info) {
   scoped_ptr<base::DictionaryValue> dict(new base::DictionaryValue());
   for (ModelSafeRoutingInfo::const_iterator it = routing_info.begin();
        it != routing_info.end(); ++it) {
     dict->SetString(ModelTypeToString(it->first),
                     ModelSafeGroupToString(it->second));
   }
   return dict;
 }
 
 std::string ModelSafeRoutingInfoToString(
     const ModelSafeRoutingInfo& routing_info) {
-  scoped_ptr<base::DictionaryValue> dict =
-      ModelSafeRoutingInfoToValue(routing_info);
   std::string json;
-  base::JSONWriter::Write(dict.get(), &json);
+  base::JSONWriter::Write(*ModelSafeRoutingInfoToValue(routing_info), &json);
   return json;
 }
 
 ModelTypeSet GetRoutingInfoTypes(const ModelSafeRoutingInfo& routing_info) {
   ModelTypeSet types;
   for (ModelSafeRoutingInfo::const_iterator it = routing_info.begin();
        it != routing_info.end(); ++it) {
     types.Put(it->first);
   }
   return types;
@@ skipping 150 matching lines @@
       return;
     DCHECK_EQ(base::MessageLoop::current(), working_loop_);
   }
 
   DCHECK(stopped_);
   base::MessageLoop::current()->RemoveDestructionObserver(this);
   unregister_done_callback.Run(GetModelSafeGroup());
 }
 
 }  // namespace syncer