Remove cruft from upload response

program/steps/mail/upload.inc

@@ -20,9 +20,8 @@
 */
 
 
-if (!$_SESSION['compose'])
+if (!$_SESSION['compose']) {
-  {
+  die("Invalid session var!");
-  exit;
 }
 
 
@@ -34,7 +33,8 @@ if (!is_array($_SESSION['compose']['attachments']))
   $_SESSION['compose']['attachments'] = array();
 
 
-$response = '';
+// clear all stored output properties (like scripts and env vars)
+$OUTPUT->reset();
 
 if (is_array($_FILES['_attachments']['tmp_name']))
   {