Auto Update Filters

Hi,

I’d like to turn the new auto update feature in WordPress 3.7 off for translation files.

In the Disabling Automatic Updates codex article, it looks like you can add the following filter to turn this functionality off.

add_filter( 'auto_update_translation', '__return_false' );

I tried adding this to my wp-config.php, and I received a PHP error in my browser when I went back to my site. What file should I add this filter to?

Thanks for your help!