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.install b/core/modules/shortcut/shortcut.install
index be6f8b2..d716a03 100644
--- a/core/modules/shortcut/shortcut.install
+++ b/core/modules/shortcut/shortcut.install
@@ -12,7 +12,6 @@
  * Implements hook_schema().
  */
 function shortcut_schema() {
-
   $schema['shortcut_set_users'] = array(
     'description' => 'Maps users to shortcut sets.',
     'fields' => array(
@@ -49,3 +48,25 @@ function shortcut_schema() {
 
   return $schema;
 }
+
+/**
+ * Implements hook_install().
+ */
+function shortcut_install() {
+  // Theme 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::service('theme_handler')->themeExists('seven')) {
+    \Drupal::config('seven.settings')->set('third_party_settings.shortcut.module_link', TRUE)->save();
+  }
+}
+
+/**
+ * Implements hook_uninstall().
+ */
+function shortcut_uninstall() {
+  // Theme settings are not configuration entities and cannot depend on modules
+  // so to unset a module-specific setting, we need to unset it with logic.
+  if (\Drupal::service('theme_handler')->themeExists('seven')) {
+    \Drupal::config('seven.settings')->clear('third_party_settings.shortcut.module_link')->save();
+  }
+}
diff --git a/core/modules/shortcut/shortcut.module b/core/modules/shortcut/shortcut.module
index cb67d4e..696a381 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)) {
+    // Theme 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/modules/system/src/Form/ThemeSettingsForm.php b/core/modules/system/src/Form/ThemeSettingsForm.php
index 44649d2..8e72246 100644
--- a/core/modules/system/src/Form/ThemeSettingsForm.php
+++ b/core/modules/system/src/Form/ThemeSettingsForm.php
@@ -182,7 +182,7 @@ public function buildForm(array $form, FormStateInterface $form_state, $theme =
       );
     }
 
-    if ((!$theme) || in_array('favicon', $features) && $this->moduleHandler->moduleExists('file')) {
+    if (((!$theme) || in_array('favicon', $features)) && $this->moduleHandler->moduleExists('file')) {
       $form['favicon'] = array(
         '#type' => 'details',
         '#title' => t('Shortcut icon settings'),
@@ -390,19 +390,19 @@ public function submitForm(array &$form, FormStateInterface $form_state) {
     // and use it in place of the default theme-provided file.
     if ($this->moduleHandler->moduleExists('file')) {
       if ($file = $values['logo_upload']) {
-        unset($values['logo_upload']);
         $filename = file_unmanaged_copy($file->getFileUri());
         $values['default_logo'] = 0;
         $values['logo_path'] = $filename;
         $values['toggle_logo'] = 1;
       }
       if ($file = $values['favicon_upload']) {
-        unset($values['favicon_upload']);
         $filename = file_unmanaged_copy($file->getFileUri());
         $values['default_favicon'] = 0;
         $values['favicon_path'] = $filename;
         $values['toggle_favicon'] = 1;
       }
+      unset($values['logo_upload']);
+      unset($values['favicon_upload']);
 
       // If the user entered a path relative to the system files directory for
       // a logo or favicon, store a public:// URI so the theme system can handle it.
diff --git a/core/modules/system/src/Tests/Batch/PageTest.php b/core/modules/system/src/Tests/Batch/PageTest.php
index 42800b7..c4b1b70 100644
--- a/core/modules/system/src/Tests/Batch/PageTest.php
+++ b/core/modules/system/src/Tests/Batch/PageTest.php
@@ -17,6 +17,15 @@
 class PageTest extends WebTestBase {
 
   /**
+   * Set to TRUE to strict check all configuration saved.
+   *
+   * @see \Drupal\Core\Config\Testing\ConfigSchemaChecker
+   *
+   * @var bool
+   */
+  protected $strictConfigSchema = TRUE;
+
+  /**
    * Modules to enable.
    *
    * @var array
diff --git a/core/modules/system/src/Tests/Entity/EntityViewControllerTest.php b/core/modules/system/src/Tests/Entity/EntityViewControllerTest.php
index aa2d800..93f75df 100644
--- a/core/modules/system/src/Tests/Entity/EntityViewControllerTest.php
+++ b/core/modules/system/src/Tests/Entity/EntityViewControllerTest.php
@@ -17,6 +17,15 @@
 class EntityViewControllerTest extends WebTestBase {
 
   /**
+   * Set to TRUE to strict check all configuration saved.
+   *
+   * @see \Drupal\Core\Config\Testing\ConfigSchemaChecker
+   *
+   * @var bool
+   */
+  protected $strictConfigSchema = TRUE;
+
+  /**
    * Modules to enable.
    *
    * @var array
diff --git a/core/modules/system/src/Tests/Extension/ThemeHandlerTest.php b/core/modules/system/src/Tests/Extension/ThemeHandlerTest.php
index 50d299c..36c17d9 100644
--- a/core/modules/system/src/Tests/Extension/ThemeHandlerTest.php
+++ b/core/modules/system/src/Tests/Extension/ThemeHandlerTest.php
@@ -19,6 +19,15 @@
 class ThemeHandlerTest extends KernelTestBase {
 
   /**
+   * Set to TRUE to strict check all configuration saved.
+   *
+   * @see \Drupal\Core\Config\Testing\ConfigSchemaChecker
+   *
+   * @var bool
+   */
+  protected $strictConfigSchema = TRUE;
+
+  /**
    * Modules to enable.
    *
    * @var array
diff --git a/core/modules/system/src/Tests/Form/FormObjectTest.php b/core/modules/system/src/Tests/Form/FormObjectTest.php
index 237d9e7..c41928a 100644
--- a/core/modules/system/src/Tests/Form/FormObjectTest.php
+++ b/core/modules/system/src/Tests/Form/FormObjectTest.php
@@ -18,6 +18,15 @@
 class FormObjectTest extends SystemConfigFormTestBase {
 
   /**
+   * Set to TRUE to strict check all configuration saved.
+   *
+   * @see \Drupal\Core\Config\Testing\ConfigSchemaChecker
+   *
+   * @var bool
+   */
+  protected $strictConfigSchema = TRUE;
+
+  /**
    * Modules to enable.
    *
    * @var array
diff --git a/core/modules/system/src/Tests/Menu/BreadcrumbTest.php b/core/modules/system/src/Tests/Menu/BreadcrumbTest.php
index ee54f31..22a2f7d 100644
--- a/core/modules/system/src/Tests/Menu/BreadcrumbTest.php
+++ b/core/modules/system/src/Tests/Menu/BreadcrumbTest.php
@@ -19,6 +19,15 @@
 class BreadcrumbTest extends MenuTestBase {
 
   /**
+   * Set to TRUE to strict check all configuration saved.
+   *
+   * @see \Drupal\Core\Config\Testing\ConfigSchemaChecker
+   *
+   * @var bool
+   */
+  protected $strictConfigSchema = TRUE;
+
+  /**
    * Modules to enable.
    *
    * @var array
@@ -41,7 +50,6 @@ protected function setUp() {
     // presence on the page, so we need to ensure that the Tools block will be
     // displayed in the admin theme.
     $this->drupalPlaceBlock('system_menu_block:tools', array(
-      'machine' => 'system_menu_tools',
       'region' => 'content',
       'theme' => \Drupal::config('system.theme')->get('admin'),
     ));
diff --git a/core/modules/system/src/Tests/Menu/MenuRouterTest.php b/core/modules/system/src/Tests/Menu/MenuRouterTest.php
index 7de9006..4dd2e19 100644
--- a/core/modules/system/src/Tests/Menu/MenuRouterTest.php
+++ b/core/modules/system/src/Tests/Menu/MenuRouterTest.php
@@ -17,6 +17,15 @@
 class MenuRouterTest extends WebTestBase {
 
   /**
+   * Set to TRUE to strict check all configuration saved.
+   *
+   * @see \Drupal\Core\Config\Testing\ConfigSchemaChecker
+   *
+   * @var bool
+   */
+  protected $strictConfigSchema = TRUE;
+
+  /**
    * Modules to enable.
    *
    * @var array
diff --git a/core/modules/system/src/Tests/System/PageTitleTest.php b/core/modules/system/src/Tests/System/PageTitleTest.php
index 98148cd..31020c9 100644
--- a/core/modules/system/src/Tests/System/PageTitleTest.php
+++ b/core/modules/system/src/Tests/System/PageTitleTest.php
@@ -20,6 +20,15 @@
 class PageTitleTest extends WebTestBase {
 
   /**
+   * Set to TRUE to strict check all configuration saved.
+   *
+   * @see \Drupal\Core\Config\Testing\ConfigSchemaChecker
+   *
+   * @var bool
+   */
+  protected $strictConfigSchema = TRUE;
+
+  /**
    * Modules to enable.
    *
    * @var array
diff --git a/core/modules/system/src/Tests/System/ThemeTest.php b/core/modules/system/src/Tests/System/ThemeTest.php
index 80d469a..8a7fd04 100644
--- a/core/modules/system/src/Tests/System/ThemeTest.php
+++ b/core/modules/system/src/Tests/System/ThemeTest.php
@@ -19,6 +19,15 @@
 class ThemeTest extends WebTestBase {
 
   /**
+   * Set to TRUE to strict check all configuration saved.
+   *
+   * @see \Drupal\Core\Config\Testing\ConfigSchemaChecker
+   *
+   * @var bool
+   */
+  protected $strictConfigSchema = TRUE;
+
+  /**
    * Modules to enable.
    *
    * @var array
diff --git a/core/modules/system/tests/modules/form_test/config/schema/form_test.schema.yml b/core/modules/system/tests/modules/form_test/config/schema/form_test.schema.yml
new file mode 100644
index 0000000..3e38933
--- /dev/null
+++ b/core/modules/system/tests/modules/form_test/config/schema/form_test.schema.yml
@@ -0,0 +1,7 @@
+form_test.object:
+  type: mapping
+  label: 'Test form'
+  mapping:
+    bananas:
+      type: string
+      label: 'Bananas'
diff --git a/core/themes/seven/config/install/seven.settings.yml b/core/themes/seven/config/install/seven.settings.yml
deleted file mode 100644
index 6bba58b..0000000
--- a/core/themes/seven/config/install/seven.settings.yml
+++ /dev/null
@@ -1,3 +0,0 @@
-third_party_settings:
-  shortcut:
-    module_link: true