upgrades core to 8.4.2

core/includes/install.inc

@@ -114,9 +114,10 @@ function drupal_install_profile_distribution_name() {
 /**
  * Loads the installation profile, extracting its defined version.
  *
- * @return string Distribution version defined in the profile's .info.yml file.
- *   Defaults to \Drupal::VERSION if no version is explicitly provided
- *   by the installation profile.
+ * @return string
+ *   Distribution version defined in the profile's .info.yml file.
+ *   Defaults to \Drupal::VERSION if no version is explicitly provided by the
+ *   installation profile.
  *
  * @see install_profile_info()
  */
@@ -530,8 +531,11 @@ function drupal_install_config_directories() {
  *
  * @deprecated in Drupal 8.1.x, will be removed before Drupal 9.0.x. Use
  *   config_get_config_directory() and file_prepare_directory() instead.
+ *
+ * @see https://www.drupal.org/node/2501187
  */
 function install_ensure_config_directory($type) {
+  @trigger_error('install_ensure_config_directory() is deprecated in Drupal 8.1.0 and will be removed before Drupal 9.0.0. Use config_get_config_directory() and file_prepare_directory() instead. See https://www.drupal.org/node/2501187.', E_USER_DEPRECATED);
   // The config directory must be defined in settings.php.
   global $config_directories;
   if (!isset($config_directories[$type])) {