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

cloud_print/gcp20/prototype/cloud_print_requester.cc

Index: cloud_print/gcp20/prototype/cloud_print_requester.cc
diff --git a/cloud_print/gcp20/prototype/cloud_print_requester.cc b/cloud_print/gcp20/prototype/cloud_print_requester.cc
index d46fdf4acc40028f6c87bd831d963b1998cc9331..cbfdae44caaa1d7195f90a8d4d0e5cfcd2b20ee9 100644
--- a/cloud_print/gcp20/prototype/cloud_print_requester.cc
+++ b/cloud_print/gcp20/prototype/cloud_print_requester.cc
@@ -86,10 +86,10 @@ std::string LocalSettingsToJson(const LocalSettings& settings) {
   current->SetBoolean("printer/local_printing_enabled",
                          settings.local_printing_enabled);
   current->SetInteger("xmpp_timeout_value", settings.xmpp_timeout_value);
-  dictionary.Set("current", current.release());
+  dictionary.Set("current", current.Pass());
 
   std::string local_settings;
-  base::JSONWriter::Write(&dictionary, &local_settings);
+  base::JSONWriter::Write(dictionary, &local_settings);
   return local_settings;
 }