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

extensions/browser/api/cast_channel/cast_channel_api.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 "extensions/browser/api/cast_channel/cast_channel_api.h"
 
 #include <limits>
 #include <string>
 
 #include "base/json/json_writer.h"
@@ skipping 41 matching lines @@
 using cast_channel::ReadyState;
 using content::BrowserThread;
 
 namespace {
 
 // T is an extension dictionary (MessageInfo or ChannelInfo)
 template <class T>
 std::string ParamToString(const T& info) {
   scoped_ptr<base::DictionaryValue> dict = info.ToValue();
   std::string out;
-  base::JSONWriter::Write(dict.get(), &out);
+  base::JSONWriter::Write(*dict, &out);
   return out;
 }
 
 // Fills |channel_info| from the destination and state of |socket|.
 void FillChannelInfo(const CastSocket& socket, ChannelInfo* channel_info) {
   DCHECK(channel_info);
   channel_info->channel_id = socket.id();
   channel_info->url = socket.cast_url();
   const net::IPEndPoint& ip_endpoint = socket.ip_endpoint();
   channel_info->connect_info.ip_address = ip_endpoint.ToStringWithoutPort();
@@ skipping 564 matching lines @@
   std::string& signature = params_->signature;
   if (signature.empty() || keys.empty() ||
       !cast_channel::SetTrustedCertificateAuthorities(keys, signature)) {
     SetError("Unable to set authority keys.");
   }
 
   AsyncWorkCompleted();
 }
 
 }  // namespace extensions