upgrades core to 8.4.2

core/includes/common.inc

@@ -252,7 +252,8 @@ function format_size($size, $langcode = NULL) {
     return \Drupal::translation()->formatPlural($size, '1 byte', '@count bytes', [], ['langcode' => $langcode]);
   }
   else {
-    $size = $size / Bytes::KILOBYTE; // Convert bytes to kilobytes.
+    // Convert bytes to kilobytes.
+    $size = $size / Bytes::KILOBYTE;
     $units = ['KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
     foreach ($units as $unit) {
       if (round($size, 2) >= Bytes::KILOBYTE) {
@@ -896,7 +897,7 @@ function drupal_render_children(&$element, $children_keys = NULL) {
   $output = '';
   foreach ($children_keys as $key) {
     if (!empty($element[$key])) {
-      $output .= drupal_render($element[$key]);
+      $output .= \Drupal::service('renderer')->render($element[$key]);
     }
   }
   return Markup::create($output);