diff --git a/core/modules/system/lib/Drupal/system/Plugin/Block/SystemBrandingBlock.php b/core/modules/system/lib/Drupal/system/Plugin/Block/SystemBrandingBlock.php
index 8e861ec..fa04d9e 100644
--- a/core/modules/system/lib/Drupal/system/Plugin/Block/SystemBrandingBlock.php
+++ b/core/modules/system/lib/Drupal/system/Plugin/Block/SystemBrandingBlock.php
@@ -8,9 +8,7 @@
 namespace Drupal\system\Plugin\Block;
 
 use Drupal\block\BlockBase;
-use Drupal\block\Annotation\Block;
-use Drupal\Core\Annotation\Translation;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
 use Drupal\Component\Utility\Xss;
 use Symfony\Component\DependencyInjection\ContainerInterface;
@@ -28,9 +26,9 @@ class SystemBrandingBlock extends BlockBase implements ContainerFactoryPluginInt
   /**
    * Stores the configuration factory.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
-  protected $configFactory;
+  protected $config_factory;
 
   /**
    * Creates a SystemBrandingBlock instance.
@@ -41,12 +39,12 @@ class SystemBrandingBlock extends BlockBase implements ContainerFactoryPluginInt
    *   The plugin_id for the plugin instance.
    * @param array $plugin_definition
    *   The plugin implementation definition.
-   * @param \Drupal\Core\Config\ConfigFactory $configFactory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The factory for configuration objects.
    */
-  public function __construct(array $configuration, $plugin_id, array $plugin_definition, ConfigFactory $configFactory) {
+  public function __construct(array $configuration, $plugin_id, array $plugin_definition, ConfigFactoryInterface $config_factory) {
     parent::__construct($configuration, $plugin_id, $plugin_definition);
-    $this->configFactory = $configFactory;
+    $this->configFactory = $config_factory;
   }
 
   /**
@@ -74,7 +72,7 @@ public function defaultConfiguration() {
   }
 
   /**
-   * Overrides \Drupal\block\BlockBase::blockForm().
+   * {@inheritdoc}
    */
   public function blockForm($form, &$form_state) {
     $form['block_branding'] = array(
@@ -103,7 +101,7 @@ public function blockForm($form, &$form_state) {
   }
 
   /**
-   * Overrides \Drupal\block\BlockBase::blockSubmit().
+   * {@inheritdoc}
    */
   public function blockSubmit($form, &$form_state) {
     $this->configuration['site_logo'] = $form_state['values']['block_branding']['site_logo'];
@@ -129,7 +127,7 @@ public function build() {
 
     // Site slogan
     $build['#use_site_slogan'] = $this->configuration['site_slogan'];
-    $build['#site_slogan'] = XSS::filterAdmin($site_config->get('slogan'));
+    $build['#site_slogan'] = Xss::filterAdmin($site_config->get('slogan'));
 
     return $build;
   }