diff --git a/core/modules/menu_link_content/src/Tests/MenuLinkContentDeriverTest.php b/core/modules/menu_link_content/src/Tests/MenuLinkContentDeriverTest.php
index 7ea61d0..b7238f8 100644
--- a/core/modules/menu_link_content/src/Tests/MenuLinkContentDeriverTest.php
+++ b/core/modules/menu_link_content/src/Tests/MenuLinkContentDeriverTest.php
@@ -69,7 +69,7 @@ public function testRediscover() {
     /** @var \Drupal\Core\Menu\MenuLinkTreeElement $tree_element */
     $tree_element = reset($menu_tree);
     $this->assertEqual('route_name_2', $tree_element->link->getRouteName());
-    $title = (string) $tree_element->link->getTitle();
+    $title = $tree_element->link->getTitle();
     $this->assertFalse($title instanceof TranslationWrapper);
     $this->assertIdentical('<script>alert("Welcome to the discovered jungle!")</script>', $title);
     $this->assertFalse(SafeMarkup::isSafe($title));
diff --git a/core/modules/system/src/Tests/Menu/MenuLinkSecurityTest.php b/core/modules/system/src/Tests/Menu/MenuLinkSecurityTest.php
index f691445..245b0c8 100644
--- a/core/modules/system/src/Tests/Menu/MenuLinkSecurityTest.php
+++ b/core/modules/system/src/Tests/Menu/MenuLinkSecurityTest.php
@@ -38,8 +38,8 @@ public function testMenuLink() {
     $this->drupalGet('<front>');
     $this->assertNoRaw('<script>alert("Wild animals")</script>');
     $this->assertNoRaw('<script>alert("Even more wild animals")</script>');
-    $this->assertRaw(htmlspecialchars('<script>alert("Wild animals")</script>', ENT_QUOTES, 'UTF-8'));
-    $this->assertRaw(htmlspecialchars('<script>alert("Even more wild animals")</script>', ENT_QUOTES, 'UTF-8'));
+    $this->assertEscaped('<script>alert("Wild animals")</script>');
+    $this->assertEscaped('<script>alert("Even more wild animals")</script>');
   }
 
 }
diff --git a/core/modules/system/system.install b/core/modules/system/system.install
index db913b7..d6799c3 100644
--- a/core/modules/system/system.install
+++ b/core/modules/system/system.install
@@ -1167,7 +1167,7 @@ function system_schema() {
 function system_update_8001(&$sandbox = NULL) {
   $database = \Drupal::database();
   $schema = $database->schema();
-  if (db_table_exists('menu_tree')) {
+  if ($schema->tableExists('menu_tree')) {
 
     if (!isset($sandbox['current'])) {
       $spec = array(