core/modules/book/book.module                       |  7 +++----
 core/modules/book/book.services.yml                 |  2 +-
 core/modules/book/src/BookExport.php                |  6 +++---
 core/modules/book/src/Controller/BookController.php | 18 +++++++++++++++---
 core/modules/system/src/Tests/Common/UrlTest.php    |  2 ++
 5 files changed, 24 insertions(+), 11 deletions(-)

diff --git a/core/modules/book/book.module b/core/modules/book/book.module
index f7ee374..e80b5e3 100644
--- a/core/modules/book/book.module
+++ b/core/modules/book/book.module
@@ -71,7 +71,7 @@ function book_theme() {
       'render element' => 'book_menus',
     ),
     'book_node_export_html' => array(
-      'variables' => array('node' => NULL, 'children' => NULL),
+      'variables' => array('node' => NULL, 'content' => NULL, 'children' => NULL),
     ),
   );
 }
@@ -234,9 +234,9 @@ function book_node_view(array &$build, EntityInterface $node, EntityViewDisplayI
       if (!$book_node->access()) {
         return;
       }
-      $book_navigation = array( '#theme' => 'book_navigation', '#book_link' => $node->book);
       $build['book_navigation'] = array(
-        '#markup' => drupal_render($book_navigation),
+        '#theme' => 'book_navigation',
+        '#book_link' => $node->book,
         '#weight' => 100,
         // The book navigation is a listing of Node entities, so associate its
         // list cache tag for correct invalidation.
@@ -491,7 +491,6 @@ function template_preprocess_book_export_html(&$variables) {
 function template_preprocess_book_node_export_html(&$variables) {
   $variables['depth'] = $variables['node']->book['depth'];
   $variables['title'] = SafeMarkup::checkPlain($variables['node']->label());
-  $variables['content'] = $variables['node']->rendered;
 }
 
 /**
diff --git a/core/modules/book/book.services.yml b/core/modules/book/book.services.yml
index 3b45dae..0a022a7 100644
--- a/core/modules/book/book.services.yml
+++ b/core/modules/book/book.services.yml
@@ -12,7 +12,7 @@ services:
     arguments: ['@book.manager']
   book.export:
     class: Drupal\book\BookExport
-    arguments: ['@entity.manager', '@book.manager']
+    arguments: ['@entity.manager', '@book.manager', '@renderer']
   book.outline_storage:
     class: Drupal\book\BookOutlineStorage
     arguments: ['@database']
diff --git a/core/modules/book/src/BookExport.php b/core/modules/book/src/BookExport.php
index b71c7a0..dbb62e9 100644
--- a/core/modules/book/src/BookExport.php
+++ b/core/modules/book/src/BookExport.php
@@ -8,6 +8,7 @@
 namespace Drupal\book;
 
 use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Render\RendererInterface;
 use Drupal\node\Entity\Node;
 use Drupal\node\NodeInterface;
 
@@ -118,7 +119,7 @@ protected function exportTraverse(array $tree, $callable) {
       }
     }
 
-    return drupal_render($build);
+    return $build;
   }
 
   /**
@@ -139,10 +140,9 @@ protected function bookNodeExport(NodeInterface $node, $children = '') {
     $build = $this->viewBuilder->view($node, 'print', NULL);
     unset($build['#theme']);
 
-    // @todo Rendering should happen in the template using render().
-    $node->rendered = drupal_render($build);
     return array(
       '#theme' => 'book_node_export_html',
+      '#content' => $build,
       '#node' => $node,
       '#children' => $children,
     );
diff --git a/core/modules/book/src/Controller/BookController.php b/core/modules/book/src/Controller/BookController.php
index 2f89937..53c64ad 100644
--- a/core/modules/book/src/Controller/BookController.php
+++ b/core/modules/book/src/Controller/BookController.php
@@ -10,6 +10,7 @@
 use Drupal\book\BookExport;
 use Drupal\book\BookManagerInterface;
 use Drupal\Core\Controller\ControllerBase;
+use Drupal\Core\Render\RendererInterface;
 use Drupal\Core\Url;
 use Drupal\node\Entity\Node;
 use Drupal\node\NodeInterface;
@@ -38,16 +39,26 @@ class BookController extends ControllerBase {
   protected $bookExport;
 
   /**
+   * The renderer.
+   *
+   * @var \Drupal\Core\Render\RendererInterface
+   */
+  protected $renderer;
+
+  /**
    * Constructs a BookController object.
    *
    * @param \Drupal\book\BookManagerInterface $bookManager
    *   The book manager.
    * @param \Drupal\book\BookExport $bookExport
    *   The book export service.
+   * @param \Drupal\Core\Render\RendererInterface $renderer
+   *   The renderer.
    */
-  public function __construct(BookManagerInterface $bookManager, BookExport $bookExport) {
+  public function __construct(BookManagerInterface $bookManager, BookExport $bookExport, RendererInterface $renderer) {
     $this->bookManager = $bookManager;
     $this->bookExport = $bookExport;
+    $this->renderer = $renderer;
   }
 
   /**
@@ -56,7 +67,8 @@ public function __construct(BookManagerInterface $bookManager, BookExport $bookE
   public static function create(ContainerInterface $container) {
     return new static(
       $container->get('book.manager'),
-      $container->get('book.export')
+      $container->get('book.export'),
+      $container->get('renderer')
     );
   }
 
@@ -154,7 +166,7 @@ public function bookExport($type, NodeInterface $node) {
     }
 
     $exported_book = $this->bookExport->{$method}($node);
-    return new Response(drupal_render($exported_book));
+    return new Response($this->renderer->renderRoot($exported_book));
   }
 
 }
diff --git a/core/modules/system/src/Tests/Common/UrlTest.php b/core/modules/system/src/Tests/Common/UrlTest.php
index 93f0503..c8e553b 100644
--- a/core/modules/system/src/Tests/Common/UrlTest.php
+++ b/core/modules/system/src/Tests/Common/UrlTest.php
@@ -9,6 +9,7 @@
 
 use Drupal\Component\Utility\UrlHelper;
 use Drupal\Core\Cache\Cache;
+use Drupal\Core\Cache\CacheableMetadata;
 use Drupal\Core\Language\Language;
 use Drupal\Core\Url;
 use Drupal\simpletest\WebTestBase;
@@ -57,6 +58,7 @@ function testLinkCacheability() {
 
     foreach ($cases as $case) {
       list($title, $uri, $options, $expected_cacheability) = $case;
+      $expected_cacheability['contexts'] = Cache::mergeContexts($expected_cacheability['contexts'], ['languages:language_interface', 'theme']);
       $link = [
         '#type' => 'link',
         '#title' => $title,