FIX: Messed up i18n key

app/helpers/email_helper.rb

@@ -13,7 +13,7 @@ module EmailHelper
   end
 
   def private_topic_title(topic)
-    I18n.t("system_messages.secure_topic_title", id: topic.id)
+    I18n.t("system_messages.private_topic_title", id: topic.id)
   end
 
   def email_topic_link(topic)

app/mailers/invite_mailer.rb

@@ -33,7 +33,7 @@ class InviteMailer < ActionMailer::Base
 
       topic_title = first_topic.try(:title)
       if SiteSetting.private_email?
-        topic_title = I18n.t("system_messages.secure_topic_title", id: first_topic.id)
+        topic_title = I18n.t("system_messages.private_topic_title", id: first_topic.id)
         topic_excerpt = ""
       end
 

config/locales/server.en.yml

@@ -1938,7 +1938,7 @@ en:
     other: "This topic is temporarily closed for %{count} hours due to a large number of community flags."
 
   system_messages:
-    secure_topic_title: "Topic #%{id}"
+    private_topic_title: "Topic #%{id}"
     contents_hidden: "Please visit the post to see its contents."
 
     post_hidden: