BUGFIX: don't show redirect reason if you aren't redirected

Move the redirect to top page logic server-side and make sure the reason
is not shown when top is not in the navigation menu (top_menu).

app/serializers/current_user_serializer.rb

@@ -17,7 +17,9 @@ class CurrentUserSerializer < BasicUserSerializer
              :can_edit,
              :can_invite_to_forum,
              :no_password,
-             :can_delete_account
+             :can_delete_account,
+             :should_be_redirected_to_top,
+             :redirected_to_top_reason
 
   def include_site_flagged_posts_count?
     object.staff?
@@ -63,4 +65,8 @@ class CurrentUserSerializer < BasicUserSerializer
     true
   end
 
+  def include_redirected_to_top_reason?
+    object.should_be_redirected_to_top
+  end
+
 end