diff --git a/core/lib/Drupal/Core/Entity/EntityListController.php b/core/lib/Drupal/Core/Entity/EntityListController.php
index f358ad3..246b73a 100644
--- a/core/lib/Drupal/Core/Entity/EntityListController.php
+++ b/core/lib/Drupal/Core/Entity/EntityListController.php
@@ -8,6 +8,7 @@
 namespace Drupal\Core\Entity;
 
 use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\StringTranslation\TranslationInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Drupal\Component\Utility\String;
 
@@ -47,6 +48,13 @@ class EntityListController implements EntityListControllerInterface, EntityContr
   protected $entityInfo;
 
   /**
+   * The translation manager service.
+   *
+   * @var \Drupal\Core\StringTranslation\TranslationInterface
+   */
+  protected $translationManager;
+
+  /**
    * {@inheritdoc}
    */
   public static function createInstance(ContainerInterface $container, $entity_type, array $entity_info) {
@@ -205,4 +213,40 @@ public function render() {
     return $build;
   }
 
+  /**
+   * Translates a string to the current language or to a given language.
+   *
+   * See the t() documentation for details.
+   */
+  protected function t($string, array $args = array(), array $options = array()) {
+    return $this->getTranslationManager()->translate($string, $args, $options);
+  }
+
+  /**
+   * Gets the translation manager.
+   *
+   * @return \Drupal\Core\StringTranslation\TranslationInterface
+   *   The translation manager.
+   */
+  protected function getTranslationManager() {
+    if (!$this->translationManager) {
+      $this->translationManager = \Drupal::translation();
+    }
+    return $this->translationManager;
+  }
+
+  /**
+   * Sets the translation manager for this form.
+   *
+   * @param \Drupal\Core\StringTranslation\TranslationInterface $translation_manager
+   *   The translation manager.
+   *
+   * @return self
+   *   The entity form.
+   */
+  public function setTranslationManager(TranslationInterface $translation_manager) {
+    $this->translationManager = $translation_manager;
+    return $this;
+  }
+
 }
diff --git a/core/lib/Drupal/Core/Form/FormBase.php b/core/lib/Drupal/Core/Form/FormBase.php
index bdb0004..400eb8d 100644
--- a/core/lib/Drupal/Core/Form/FormBase.php
+++ b/core/lib/Drupal/Core/Form/FormBase.php
@@ -48,20 +48,7 @@ public function validateForm(array &$form, array &$form_state) {
   /**
    * Translates a string to the current language or to a given language.
    *
-   * @param string $string
-   *   A string containing the English string to translate.
-   * @param array $args
-   *   An associative array of replacements to make after translation. Based
-   *   on the first character of the key, the value is escaped and/or themed.
-   *   See \Drupal\Core\Utility\String::format() for details.
-   * @param array $options
-   *   An associative array of additional options, with the following elements:
-   *   - 'langcode': The language code to translate to a language other than
-   *      what is used to display the page.
-   *   - 'context': The context the source string belongs to.
-   *
-   * @return string
-   *   The translated string.
+   * See the t() documentation for details.
    */
   protected function t($string, array $args = array(), array $options = array()) {
     return $this->getTranslationManager()->translate($string, $args, $options);
diff --git a/core/lib/Drupal/Core/Menu/Plugin/Derivative/StaticLocalActionDeriver.php b/core/lib/Drupal/Core/Menu/Plugin/Derivative/StaticLocalActionDeriver.php
index 166089d..e9ef0ee 100644
--- a/core/lib/Drupal/Core/Menu/Plugin/Derivative/StaticLocalActionDeriver.php
+++ b/core/lib/Drupal/Core/Menu/Plugin/Derivative/StaticLocalActionDeriver.php
@@ -10,7 +10,7 @@
 use Drupal\Core\Extension\ModuleHandlerInterface;
 use Drupal\Core\Plugin\Discovery\ContainerDerivativeInterface;
 use Drupal\Component\Plugin\Exception\PluginException;
-use Drupal\Core\StringTranslation\TranslationManager;
+use Drupal\Core\StringTranslation\TranslationInterface;
 use Drupal\Component\Utility\String;
 use Drupal\Component\Discovery\YamlDiscovery;
 use Symfony\Component\DependencyInjection\ContainerInterface;
@@ -44,7 +44,7 @@ class StaticLocalActionDeriver implements ContainerDerivativeInterface {
   /**
    * The translation manager.
    *
-   * @var \Drupal\Core\StringTranslation\TranslationManager
+   * @var \Drupal\Core\StringTranslation\TranslationInterface
    */
   protected $translationManager;
 
@@ -66,10 +66,10 @@ public static function create(ContainerInterface $container, $base_plugin_id) {
    *   The base plugin ID.
    * @param\Drupal\Core\Extension\ModuleHandlerInterface $module_handler
    *   The module handler.
-   * @param \Drupal\Core\StringTranslation\TranslationManager translation_manager
+   * @param \Drupal\Core\StringTranslation\TranslationInterface translation_manager
    *   The translation manager.
    */
-  public function __construct($base_plugin_id, ModuleHandlerInterface $module_handler, TranslationManager $translation_manager) {
+  public function __construct($base_plugin_id, ModuleHandlerInterface $module_handler, TranslationInterface $translation_manager) {
     $this->basePluginId = $base_plugin_id;
     $this->moduleHandler = $module_handler;
     $this->translationManager = $translation_manager;
@@ -103,7 +103,7 @@ public function getDerivativeDefinitions(array $base_plugin_definition) {
           $info += array('provider' => $module);
           // Make sure 'appears_on' is an array.
           $info['appears_on'] = (array) $info['appears_on'];
-          $info['title'] = $this->translationManager->translate($info['title']);
+          $info['title'] = $this->t($info['title']);
           $this->derivatives[$name] = $info + $base_plugin_definition;
         }
       }
@@ -112,4 +112,13 @@ public function getDerivativeDefinitions(array $base_plugin_definition) {
     return $this->derivatives;
   }
 
+  /**
+   * Translates a string to the current language or to a given language.
+   *
+   * See the t() documentation for details.
+   */
+  protected function t($string, array $args = array(), array $options = array()) {
+    return $this->translationManager->translate($string, $args, $options);
+  }
+
 }
diff --git a/core/modules/aggregator/lib/Drupal/aggregator/Plugin/Derivative/AggregatorCategoryBlock.php b/core/modules/aggregator/lib/Drupal/aggregator/Plugin/Derivative/AggregatorCategoryBlock.php
index 8f096fb..57a5a7c 100644
--- a/core/modules/aggregator/lib/Drupal/aggregator/Plugin/Derivative/AggregatorCategoryBlock.php
+++ b/core/modules/aggregator/lib/Drupal/aggregator/Plugin/Derivative/AggregatorCategoryBlock.php
@@ -9,7 +9,7 @@
 
 use Drupal\Core\Plugin\Discovery\ContainerDerivativeInterface;
 use Drupal\Core\Database\Connection;
-use Drupal\Core\StringTranslation\Translator\TranslatorInterface;
+use Drupal\Core\StringTranslation\TranslationInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
@@ -43,7 +43,7 @@ class AggregatorCategoryBlock implements ContainerDerivativeInterface {
   /**
    * The translation manager.
    *
-   * @var \Drupal\Core\StringTranslation\Translator\TranslatorInterface
+   * @var \Drupal\Core\StringTranslation\TranslationInterface
    */
   protected $translationManager;
 
@@ -54,10 +54,10 @@ class AggregatorCategoryBlock implements ContainerDerivativeInterface {
    *   The base plugin ID.
    * @param \Drupal\Core\Database\Connection $connection
    *   The database connection.
-   * @param \Drupal\Core\StringTranslation\Translator\TranslatorInterface $translation_manager
+   * @param \Drupal\Core\StringTranslation\TranslationInterface $translation_manager
    *   The translation manager.
    */
-  public function __construct($base_plugin_id, Connection $connection, TranslatorInterface $translation_manager) {
+  public function __construct($base_plugin_id, Connection $connection, TranslationInterface $translation_manager) {
     $this->basePluginId = $base_plugin_id;
     $this->connection = $connection;
     $this->translationManager = $translation_manager;
@@ -83,7 +83,7 @@ public function getDerivativeDefinition($derivative_id, array $base_plugin_defin
     }
     $result = $this->connection->query('SELECT cid, title FROM {aggregator_category} ORDER BY title WHERE cid = :cid', array(':cid' => $derivative_id))->fetchObject();
     $this->derivatives[$derivative_id] = $base_plugin_definition;
-    $this->derivatives[$derivative_id]['admin_label'] = $this->translationManager->translate('@title category latest items', array('@title' => $result->title));
+    $this->derivatives[$derivative_id]['admin_label'] = $this->t('@title category latest items', array('@title' => $result->title));
     return $this->derivatives[$derivative_id];
   }
 
@@ -95,9 +95,18 @@ public function getDerivativeDefinitions(array $base_plugin_definition) {
     $result = $this->connection->query('SELECT cid, title FROM {aggregator_category} ORDER BY title');
     foreach ($result as $category) {
       $this->derivatives[$category->cid] = $base_plugin_definition;
-      $this->derivatives[$category->cid]['admin_label'] = $this->translationManager->translate('@title category latest items', array('@title' => $category->title));
+      $this->derivatives[$category->cid]['admin_label'] = $this->t('@title category latest items', array('@title' => $category->title));
     }
     return $this->derivatives;
   }
 
+  /**
+   * Translates a string to the current language or to a given language.
+   *
+   * See the t() documentation for details.
+   */
+  protected function t($string, array $args = array(), array $options = array()) {
+    return $this->translationManager->translate($string, $args, $options);
+  }
+
 }
diff --git a/core/modules/config/lib/Drupal/config/Controller/ConfigController.php b/core/modules/config/lib/Drupal/config/Controller/ConfigController.php
index 13917c0..1eb40f3 100644
--- a/core/modules/config/lib/Drupal/config/Controller/ConfigController.php
+++ b/core/modules/config/lib/Drupal/config/Controller/ConfigController.php
@@ -10,7 +10,6 @@
 use Drupal\Core\Controller\ControllerInterface;
 use Drupal\Core\Config\StorageInterface;
 use Drupal\Component\Archiver\ArchiveTar;
-use Drupal\Core\Extension\ModuleHandlerInterface;
 use Drupal\system\FileDownloadController;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\HttpFoundation\Request;
@@ -37,7 +36,7 @@ class ConfigController implements ControllerInterface {
   /**
    * The file download controller.
    *
-   * @var \Drupal\Core\Controller\ControllerInterface
+   * @var \Drupal\system\FileDownloadController
    */
   protected $fileDownloadController;
 
@@ -45,10 +44,12 @@ class ConfigController implements ControllerInterface {
    * {@inheritdoc}
    */
   public static function create(ContainerInterface $container) {
+    $file_download = new FileDownloadController();
+    $file_download->setContainer($container);
     return new static(
       $container->get('config.storage'),
       $container->get('config.storage.staging'),
-      FileDownloadController::create($container)
+      $file_download
     );
   }
 
@@ -59,10 +60,10 @@ public static function create(ContainerInterface $container) {
    *   The target storage.
    * @param \Drupal\Core\Config\StorageInterface $source_storage
    *   The source storage
-   * @param \Drupal\Core\Controller\ControllerInterface $file_download_controller
+   * @param \Drupal\system\FileDownloadController $file_download_controller
    *   The file download controller.
    */
-  public function __construct(StorageInterface $target_storage, StorageInterface $source_storage, ControllerInterface $file_download_controller) {
+  public function __construct(StorageInterface $target_storage, StorageInterface $source_storage, FileDownloadController $file_download_controller) {
     $this->targetStorage = $target_storage;
     $this->sourceStorage = $source_storage;
     $this->fileDownloadController = $file_download_controller;
diff --git a/core/modules/image/lib/Drupal/image/Controller/ImageStyleDownloadController.php b/core/modules/image/lib/Drupal/image/Controller/ImageStyleDownloadController.php
index 8013962..6820dc8 100644
--- a/core/modules/image/lib/Drupal/image/Controller/ImageStyleDownloadController.php
+++ b/core/modules/image/lib/Drupal/image/Controller/ImageStyleDownloadController.php
@@ -8,12 +8,9 @@
 namespace Drupal\image\Controller;
 
 use Drupal\Component\Utility\Crypt;
-use Drupal\Core\Config\ConfigFactory;
 use Drupal\Core\Controller\ControllerInterface;
-use Drupal\Core\Extension\ModuleHandlerInterface;
 use Drupal\Core\Image\ImageFactory;
 use Drupal\Core\Lock\LockBackendInterface;
-use Drupal\Core\StringTranslation\Translator\TranslatorInterface;
 use Drupal\image\ImageStyleInterface;
 use Drupal\system\FileDownloadController;
 use Symfony\Component\DependencyInjection\ContainerInterface;
@@ -29,13 +26,6 @@
 class ImageStyleDownloadController extends FileDownloadController implements ControllerInterface {
 
   /**
-   * The config factory.
-   *
-   * @var \Drupal\Core\config\ConfigFactory
-   */
-  protected $configFactory;
-
-  /**
    * The lock backend.
    *
    * @var \Drupal\Core\Lock\LockBackendInterface
@@ -43,13 +33,6 @@ class ImageStyleDownloadController extends FileDownloadController implements Con
   protected $lock;
 
   /**
-   * The translator service.
-   *
-   * @var \Drupal\Core\StringTranslation\Translator\TranslatorInterface
-   */
-  protected $translator;
-
-  /**
    * The image factory.
    *
    * @var \Drupal\Core\Image\ImageFactory
@@ -59,22 +42,13 @@ class ImageStyleDownloadController extends FileDownloadController implements Con
   /**
    * Constructs a ImageStyleDownloadController object.
    *
-   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
-   *   The module handler.
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
-   *   The config factory.
    * @param \Drupal\Core\Lock\LockBackendInterface $lock
    *   The lock backend.
-   * @param \Drupal\Core\StringTranslation\Translator\TranslatorInterface $translator
-   *   The translator service.
    * @param \Drupal\Core\Image\ImageFactory $image_factory
    *   The image factory.
    */
-  public function __construct(ModuleHandlerInterface $module_handler, ConfigFactory $config_factory, LockBackendInterface $lock, TranslatorInterface $translator, ImageFactory $image_factory) {
-    parent::__construct($module_handler);
-    $this->configFactory = $config_factory;
+  public function __construct(LockBackendInterface $lock, ImageFactory $image_factory) {
     $this->lock = $lock;
-    $this->translator = $translator;
     $this->imageFactory = $image_factory;
   }
 
@@ -83,10 +57,7 @@ public function __construct(ModuleHandlerInterface $module_handler, ConfigFactor
    */
   public static function create(ContainerInterface $container) {
     return new static(
-      $container->get('module_handler'),
-      $container->get('config.factory'),
       $container->get('lock'),
-      $container->get('string_translation'),
       $container->get('image.factory')
     );
   }
@@ -105,6 +76,8 @@ public static function create(ContainerInterface $container) {
    *
    * @throws \Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException
    *   Thrown when the user does not have access to the file.
+   * @throws \Symfony\Component\HttpKernel\Exception\ServiceUnavailableHttpException
+   *   Thrown when the file is still being generated.
    *
    * @return \Symfony\Component\HttpFoundation\BinaryFileResponse|\Symfony\Component\HttpFoundation\Response
    *   The transferred file as response or some error response.
@@ -120,7 +93,7 @@ public function deliver(Request $request, $scheme, ImageStyleInterface $image_st
     // bypass the latter check, but this will increase the site's vulnerability
     // to denial-of-service attacks.
     $valid = !empty($image_style) && file_stream_wrapper_valid_scheme($scheme);
-    if (!$this->configFactory->get('image.settings')->get('allow_insecure_derivatives')) {
+    if (!$this->config('image.settings')->get('allow_insecure_derivatives')) {
       $valid &= $request->query->get(IMAGE_DERIVATIVE_TOKEN) === $image_style->getPathToken($image_uri);
     }
     if (!$valid) {
@@ -137,7 +110,7 @@ public function deliver(Request $request, $scheme, ImageStyleInterface $image_st
         return parent::download($request, $scheme);
       }
       else {
-        $headers = $this->moduleHandler->invokeAll('file_download', array($image_uri));
+        $headers = $this->moduleHandler()->invokeAll('file_download', array($image_uri));
         if (in_array(-1, $headers) || empty($headers)) {
           throw new AccessDeniedHttpException();
         }
@@ -147,7 +120,7 @@ public function deliver(Request $request, $scheme, ImageStyleInterface $image_st
     // Don't try to generate file if source is missing.
     if (!file_exists($image_uri)) {
       watchdog('image', 'Source image at %source_image_path not found while trying to generate derivative image at %derivative_path.',  array('%source_image_path' => $image_uri, '%derivative_path' => $derivative_uri));
-      return new Response($this->translator->translate('Error generating image, missing source file.'), 404);
+      return new Response($this->t('Error generating image, missing source file.'), 404);
     }
 
     // Don't start generating the image if the derivative already exists or if
@@ -158,7 +131,7 @@ public function deliver(Request $request, $scheme, ImageStyleInterface $image_st
       if (!$lock_acquired) {
         // Tell client to retry again in 3 seconds. Currently no browsers are
         // known to support Retry-After.
-        throw new ServiceUnavailableHttpException(3, $this->translator->translate('Image generation in progress. Try again shortly.'));
+        throw new ServiceUnavailableHttpException(3, $this->t('Image generation in progress. Try again shortly.'));
       }
     }
 
@@ -181,7 +154,7 @@ public function deliver(Request $request, $scheme, ImageStyleInterface $image_st
     }
     else {
       watchdog('image', 'Unable to generate the derived image located at %path.', array('%path' => $derivative_uri));
-      return new Response($this->translator->translate('Error generating image.'), 500);
+      return new Response($this->t('Error generating image.'), 500);
     }
   }
 
diff --git a/core/modules/image/lib/Drupal/image/ImageStyleListController.php b/core/modules/image/lib/Drupal/image/ImageStyleListController.php
index 014ab1f..f6a2534 100644
--- a/core/modules/image/lib/Drupal/image/ImageStyleListController.php
+++ b/core/modules/image/lib/Drupal/image/ImageStyleListController.php
@@ -29,13 +29,6 @@ class ImageStyleListController extends ConfigEntityListController implements Ent
   protected $urlGenerator;
 
   /**
-   * The translation manager service.
-   *
-   * @var \Drupal\Core\StringTranslation\Translator\TranslatorInterface
-   */
-  protected $translator;
-
-  /**
    * Constructs a new ImageStyleListController object.
    *
    * @param string $entity_type
@@ -48,13 +41,10 @@ class ImageStyleListController extends ConfigEntityListController implements Ent
    *   The module handler to invoke hooks on.
    * @param \Drupal\Core\Routing\UrlGeneratorInterface $url_generator
    *   The URL generator.
-   * @param \Drupal\Core\StringTranslation\Translator\TranslatorInterface $translator
-   *   The translation manager.
    */
-  public function __construct($entity_type, array $entity_info, EntityStorageControllerInterface $image_style_storage, ModuleHandlerInterface $module_handler, UrlGeneratorInterface $url_generator, TranslatorInterface $translator) {
+  public function __construct($entity_type, array $entity_info, EntityStorageControllerInterface $image_style_storage, ModuleHandlerInterface $module_handler, UrlGeneratorInterface $url_generator) {
     parent::__construct($entity_type, $entity_info, $image_style_storage, $module_handler);
     $this->urlGenerator = $url_generator;
-    $this->translator = $translator;
   }
 
   /**
@@ -75,7 +65,7 @@ public static function createInstance(ContainerInterface $container, $entity_typ
    * {@inheritdoc}
    */
   public function buildHeader() {
-    $header['label'] = $this->translator->translate('Style name');
+    $header['label'] = $this->t('Style name');
     return $header + parent::buildHeader();
   }
 
@@ -92,7 +82,7 @@ public function buildRow(EntityInterface $entity) {
    */
   public function render() {
     $build = parent::render();
-    $build['#empty'] = $this->translator->translate('There are currently no styles. <a href="!url">Add a new one</a>.', array(
+    $build['#empty'] = $this->t('There are currently no styles. <a href="!url">Add a new one</a>.', array(
       '!url' => $this->urlGenerator->generateFromPath('admin/config/media/image-styles/add'),
     ));
     return $build;
diff --git a/core/modules/system/lib/Drupal/system/FileDownloadController.php b/core/modules/system/lib/Drupal/system/FileDownloadController.php
index 8bff1bb..a65342d 100644
--- a/core/modules/system/lib/Drupal/system/FileDownloadController.php
+++ b/core/modules/system/lib/Drupal/system/FileDownloadController.php
@@ -7,9 +7,7 @@
 
 namespace Drupal\system;
 
-use Drupal\Core\Controller\ControllerInterface;
-use Drupal\Core\Extension\ModuleHandlerInterface;
-use Symfony\Component\DependencyInjection\ContainerInterface;
+use Drupal\Core\Controller\ControllerBase;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException;
 use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
@@ -18,33 +16,7 @@
 /**
  * System file controller.
  */
-class FileDownloadController implements ControllerInterface {
-
-  /**
-   * The module handler.
-   *
-   * @var \Drupal\Core\Extension\ModuleHandlerInterface
-   */
-  protected $moduleHandler;
-
-  /**
-   * Constructs a FileDownloadController object.
-   *
-   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
-   *   The module handler.
-   */
-  public function __construct(ModuleHandlerInterface $module_handler) {
-    $this->moduleHandler = $module_handler;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public static function create(ContainerInterface $container) {
-    return new static(
-      $container->get('module_handler')
-    );
-  }
+class FileDownloadController extends ControllerBase {
 
   /**
    * Handles private file transfers.
@@ -78,7 +50,7 @@ public function download(Request $request, $scheme = 'private') {
 
     if (file_stream_wrapper_valid_scheme($scheme) && file_exists($uri)) {
       // Let other modules provide headers and controls access to the file.
-      $headers = $this->moduleHandler->invokeAll('file_download', array($uri));
+      $headers = $this->moduleHandler()->invokeAll('file_download', array($uri));
 
       foreach ($headers as $result) {
         if ($result == -1) {