move write_debug to the right position

write_debug isn't executed if an exception is catched.

controllers/feed.php

@@ -193,6 +193,8 @@ Router\action('subscribe', function() {
         $error_message = t('Unable to detect the feed format.');
     }
 
+    Model\Config\write_debug();
+
     if (isset($feed_id) && $feed_id !== false) {
         Session\flash(t('Subscription added successfully.'));
         Response\redirect('?action=feed-items&feed_id='.$feed_id);

models/feed.php

@@ -198,8 +198,6 @@ function create($url, $enable_grabber = false, $force_rtl = false, $cloak_referr
         fetch_favicon($feed_id, $feed->getSiteUrl(), $feed->getIcon());
     }
 
-    Config\write_debug();
-
     return $feed_id;
 }