diff --git a/core/modules/rdf/src/Entity/RdfMapping.php b/core/modules/rdf/src/Entity/RdfMapping.php
index af4e307..577cbe7 100644
--- a/core/modules/rdf/src/Entity/RdfMapping.php
+++ b/core/modules/rdf/src/Entity/RdfMapping.php
@@ -51,31 +51,27 @@ class RdfMapping extends ConfigEntityBase implements RdfMappingInterface {
    *
    * @var array
    */
-  protected $types;
+  protected $types = array();
 
   /**
    * The mappings for fields on this bundle.
    *
    * @var array
    */
-  protected $fieldMappings;
+  protected $fieldMappings = array();
 
   /**
    * {@inheritdoc}
    */
   public function getPreparedBundleMapping() {
-    $types = array();
-    if (isset($this->types)) {
-      $types = $this->types;
-    }
-    return array('types' => $types);
+    return array('types' => $this->types);
   }
 
   /**
    * {@inheritdoc}
    */
   public function getBundleMapping() {
-    if (isset($this->types)) {
+    if (!empty($this->types)) {
       return array('types' => $this->types);
     }
     return array();
diff --git a/core/modules/shortcut/shortcut.module b/core/modules/shortcut/shortcut.module
index cb67d4e..7f0dbf8 100644
--- a/core/modules/shortcut/shortcut.module
+++ b/core/modules/shortcut/shortcut.module
@@ -396,3 +396,16 @@ function shortcut_toolbar() {
 
   return $items;
 }
+
+/**
+ * Implements hook_themes_installed().
+ */
+function shortcut_themes_installed($theme_list) {
+  if (in_array('seven', $theme_list)) {
+    // Themes settings are not configuration entities and cannot depend on modules
+    // so to set a module specific setting, we need to set it with logic.
+    if (\Drupal::moduleHandler()->moduleExists('shortcut')) {
+      \Drupal::config('seven.settings')->set('third_party_settings.shortcut.module_link', TRUE)->save();
+    }
+  }
+}
diff --git a/core/themes/seven/seven.install b/core/themes/seven/seven.install
index 43faf47b..e69de29 100644
--- a/core/themes/seven/seven.install
+++ b/core/themes/seven/seven.install
@@ -1,17 +0,0 @@
-<?php
-
-/**
- * @file
- * Install, update and uninstall functions for the seven theme.
- */
-
-/**
- * Implements hook_install().
- */
-function seven_install() {
-  // Themes settings are not configuration entities and cannot depend on modules
-  // so to set a module specific setting, we need to set it with logic.
-  if (\Drupal::moduleHandler()->moduleExists('shortcut')) {
-    \Drupal::config('seven.settings')->set('third_party_settings.shortcut.module_link', TRUE)->save();
-  }
-}