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

remoting/host/host_config.cc

Index: remoting/host/host_config.cc
diff --git a/remoting/host/host_config.cc b/remoting/host/host_config.cc
index 40ae940b46770eb03dd8d45f9b7a4b516120c848..2250d6fc4f715fb2bf8eb63466e8ea50a57b25c1 100644
--- a/remoting/host/host_config.cc
+++ b/remoting/host/host_config.cc
@@ -28,7 +28,7 @@ scoped_ptr<base::DictionaryValue> HostConfigFromJson(
 
 std::string HostConfigToJson(const base::DictionaryValue& host_config) {
   std::string data;
-  base::JSONWriter::Write(&host_config, &data);
+  base::JSONWriter::Write(host_config, &data);
   return data;
 }