Issue #1587858 by apotek: Fixed AJAX alert dialogs respect neither...

Issue #1587858 by apotek: Fixed AJAX alert dialogs respect neither display_errors() ini.php setting or ['error_level()'] setting, exposing server info.

core/includes/errors.inc

@@ -227,8 +227,10 @@ function _drupal_log_error($error, $fatal = FALSE) {
 
   if (isset($_SERVER['HTTP_X_REQUESTED_WITH']) && $_SERVER['HTTP_X_REQUESTED_WITH'] == 'XMLHttpRequest') {
     if ($fatal) {
-      // When called from JavaScript, simply output the error message.
-      print t('%type: !message in %function (line %line of %file).', $error);
+      if (error_displayable($error)) {
+        // When called from JavaScript, simply output the error message.
+        print t('%type: !message in %function (line %line of %file).', $error);
+      }
       exit;
     }
   }