diff --git a/core/core.services.yml b/core/core.services.yml
index 5613f5e..e951e55 100644
--- a/core/core.services.yml
+++ b/core/core.services.yml
@@ -102,7 +102,7 @@ services:
     arguments: ['@config.storage', '@config.storage.schema', '@cache.config']
   cron:
     class: Drupal\Core\Cron
-    arguments: ['@module_handler', '@lock', '@queue', '@state']
+    arguments: ['@module_handler', '@lock', '@queue', '@state', '@current_user']
   database:
     class: Drupal\Core\Database\Connection
     factory_class: Drupal\Core\Database\Database
@@ -412,7 +412,7 @@ services:
       - [setContainer, ['@service_container']]
     tags:
       - { name: route_enhancer, priority: 1000 }
-    arguments: ['@authentication']
+    arguments: ['@authentication', '@current_user']
   route_enhancer.entity:
     class: Drupal\Core\Entity\Enhancer\EntityRouteEnhancer
     arguments: ['@controller_resolver', '@entity.manager', '@form_builder']
@@ -716,11 +716,10 @@ services:
       - { name: event_subscriber }
     arguments: ['@authentication']
   current_user:
-    class: Drupal\Core\Session\AccountInterface
-    factory_method: authenticate
-    factory_service: authentication
-    arguments: ['@request']
-    synchronized: true
+    class: Drupal\Core\Session\AccountProxy
+    arguments: ['@authentication']
+    calls:
+      - [setRequest, ['@?request=']]
   asset.css.collection_renderer:
     class: Drupal\Core\Asset\CssCollectionRenderer
     arguments: [ '@state' ]
diff --git a/core/lib/Drupal.php b/core/lib/Drupal.php
index e1ae91a..7b9c326 100644
--- a/core/lib/Drupal.php
+++ b/core/lib/Drupal.php
@@ -190,7 +190,7 @@ public static function request() {
   /**
    * Gets the current active user.
    *
-   * @return \Drupal\Core\Session\AccountInterface
+   * @return \Drupal\Core\Session\AccountProxyInterface
    */
   public static function currentUser() {
     return static::$container->get('current_user');
diff --git a/core/lib/Drupal/Core/Authentication/AuthenticationManagerInterface.php b/core/lib/Drupal/Core/Authentication/AuthenticationManagerInterface.php
index b547edd..0b4c0ff 100644
--- a/core/lib/Drupal/Core/Authentication/AuthenticationManagerInterface.php
+++ b/core/lib/Drupal/Core/Authentication/AuthenticationManagerInterface.php
@@ -10,7 +10,7 @@
 /**
  * Defines an interface for authentication managers.
  */
-interface AuthenticationManagerInterface {
+interface AuthenticationManagerInterface extends AuthenticationProviderInterface {
 
   /**
    * Returns the service id of the default authentication provider.
@@ -19,4 +19,5 @@
    *   The service id of the default authentication provider.
    */
   public function defaultProviderId();
+
 }
diff --git a/core/lib/Drupal/Core/Cron.php b/core/lib/Drupal/Core/Cron.php
index 374d735..6bf463e 100644
--- a/core/lib/Drupal/Core/Cron.php
+++ b/core/lib/Drupal/Core/Cron.php
@@ -11,6 +11,7 @@
 use Drupal\Core\KeyValueStore\StateInterface;
 use Drupal\Core\Lock\LockBackendInterface;
 use Drupal\Core\Queue\QueueFactory;
+use Drupal\Core\Session\AccountProxyInterface;
 use Drupal\Core\Session\AnonymousUserSession;
 
 /**
@@ -47,6 +48,13 @@ class Cron implements CronInterface {
   protected $state;
 
   /**
+   * The current user.
+   *
+   * @var \Drupal\Core\Session\AccountProxyInterface
+   */
+  protected $currentUser;
+
+  /**
    * Constructs a cron object.
    *
    * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
@@ -57,12 +65,15 @@ class Cron implements CronInterface {
    *   The queue service.
    * @param \Drupal\Core\KeyValueStore\StateInterface $state
    *   The state service.
+   * @param \Drupal\Core\Session\AccountProxyInterface $current_user
+   *    The current user.
    */
-  public function __construct(ModuleHandlerInterface $module_handler, LockBackendInterface $lock, QueueFactory $queue_factory, StateInterface $state) {
+  public function __construct(ModuleHandlerInterface $module_handler, LockBackendInterface $lock, QueueFactory $queue_factory, StateInterface $state, AccountProxyInterface $current_user) {
     $this->moduleHandler = $module_handler;
     $this->lock = $lock;
     $this->queueFactory = $queue_factory;
     $this->state = $state;
+    $this->currentUser = $current_user;
   }
 
   /**
@@ -78,10 +89,8 @@ public function run() {
 
     // Force the current user to anonymous to ensure consistent permissions on
     // cron runs.
-    // @todo This currently does not work, as it will not affect the current
-    //   user being injected into services.
-    $original_user = $GLOBALS['user'];
-    $GLOBALS['user'] = new AnonymousUserSession();
+    $original_user = $this->currentUser->getAccount();
+    $this->currentUser->setAccount(new AnonymousUserSession());
 
     // Try to allocate enough time to run all the hook_cron implementations.
     drupal_set_time_limit(240);
@@ -147,9 +156,7 @@ public function run() {
     }
 
     // Restore the user.
-    // @todo This currently does not work, as it will not affect the current
-    //   user being injected into services.
-    $GLOBALS['user'] = $original_user;
+    $this->currentUser->setAccount($original_user);
     drupal_save_session($original_session_saving);
 
     return $return;
diff --git a/core/lib/Drupal/Core/Entity/EntityAccessController.php b/core/lib/Drupal/Core/Entity/EntityAccessController.php
index 835bb5a..b43c112 100644
--- a/core/lib/Drupal/Core/Entity/EntityAccessController.php
+++ b/core/lib/Drupal/Core/Entity/EntityAccessController.php
@@ -269,7 +269,7 @@ protected function checkCreateAccess(AccountInterface $account, array $context,
    */
   protected function prepareUser(AccountInterface $account = NULL) {
     if (!$account) {
-      $account = $GLOBALS['user'];
+      $account = \Drupal::currentUser();
     }
     return $account;
   }
diff --git a/core/lib/Drupal/Core/EventSubscriber/AuthenticationSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/AuthenticationSubscriber.php
index a2aa7d8..87a3cfe 100644
--- a/core/lib/Drupal/Core/EventSubscriber/AuthenticationSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/AuthenticationSubscriber.php
@@ -10,7 +10,6 @@
 use Drupal\Core\Authentication\AuthenticationProviderInterface;
 use Symfony\Component\HttpKernel\HttpKernelInterface;
 use Symfony\Component\HttpKernel\KernelEvents;
-use Symfony\Component\HttpKernel\Event\GetResponseEvent;
 use Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent;
 use Symfony\Component\HttpKernel\Event\FilterResponseEvent;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
@@ -40,18 +39,6 @@ public function __construct(AuthenticationProviderInterface $authentication_prov
   }
 
   /**
-   * Authenticates user on request.
-   *
-   * @see \Drupal\Core\Authentication\AuthenticationProviderInterface::authenticate()
-   */
-  public function onKernelRequestAuthenticate(GetResponseEvent $event) {
-    if ($event->getRequestType() == HttpKernelInterface::MASTER_REQUEST) {
-      $request = $event->getRequest();
-      $this->authenticationProvider->authenticate($request);
-    }
-  }
-
-  /**
    * Triggers authentication clean up on response.
    *
    * @see \Drupal\Core\Authentication\AuthenticationProviderInterface::cleanup()
@@ -83,9 +70,6 @@ public function onException(GetResponseForExceptionEvent $event) {
    * Cookie provider to send all relevant session data to the user.
    */
   public static function getSubscribedEvents() {
-    // Priority must be higher than LanguageRequestSubscriber as LanguageManager
-    // access current user in case language module enabled.
-    $events[KernelEvents::REQUEST][] = array('onKernelRequestAuthenticate', 300);
     $events[KernelEvents::RESPONSE][] = array('onRespond', 0);
     $events[KernelEvents::EXCEPTION][] = array('onException', 0);
     return $events;
diff --git a/core/lib/Drupal/Core/Routing/Enhancer/AuthenticationEnhancer.php b/core/lib/Drupal/Core/Routing/Enhancer/AuthenticationEnhancer.php
index b9c477d..125d9c8 100644
--- a/core/lib/Drupal/Core/Routing/Enhancer/AuthenticationEnhancer.php
+++ b/core/lib/Drupal/Core/Routing/Enhancer/AuthenticationEnhancer.php
@@ -8,6 +8,7 @@
 namespace Drupal\Core\Routing\Enhancer;
 
 use Drupal\Core\Authentication\AuthenticationManagerInterface;
+use Drupal\Core\Session\AccountProxyInterface;
 use Drupal\Core\Session\AnonymousUserSession;
 use Symfony\Cmf\Component\Routing\Enhancer\RouteEnhancerInterface;
 use Symfony\Component\DependencyInjection\ContainerAware;
@@ -32,13 +33,23 @@ class AuthenticationEnhancer extends ContainerAware implements RouteEnhancerInte
   protected $manager;
 
   /**
+   * The current user service.
+   *
+   * @var \Drupal\Core\Session\AccountProxyInterface
+   */
+  protected $currentUser;
+
+  /**
    * Constructs a AuthenticationEnhancer object.
    *
-   * @param AuthenticationManagerInterface $manager
+   * @param \Drupal\Core\Authentication\AuthenticationManagerInterface $manager
    *   The authentication manager.
+   * @param \Drupal\Core\Session\AccountProxyInterface $current_user
+   *   The current user service.
    */
-  function __construct(AuthenticationManagerInterface $manager) {
+  function __construct(AuthenticationManagerInterface $manager, AccountProxyInterface $current_user) {
     $this->manager = $manager;
+    $this->currentUser = $current_user;
   }
 
   /**
@@ -55,7 +66,7 @@ public function enhance(array $defaults, Request $request) {
       if (!in_array($auth_provider_triggered, $auth_providers)) {
         $anonymous_user = new AnonymousUserSession();
 
-        $this->container->set('current_user', $anonymous_user, 'request');
+        $this->currentUser->setAccount($anonymous_user);
 
         // The global $user object is included for backward compatibility only
         // and should be considered deprecated.
diff --git a/core/lib/Drupal/Core/Session/AccountProxy.php b/core/lib/Drupal/Core/Session/AccountProxy.php
new file mode 100644
index 0000000..8c385dd
--- /dev/null
+++ b/core/lib/Drupal/Core/Session/AccountProxy.php
@@ -0,0 +1,198 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Session\AccountProxy.
+ */
+
+namespace Drupal\Core\Session;
+
+use Drupal\Core\Authentication\AuthenticationManagerInterface;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * A proxied implementation of AccountInterface.
+ *
+ * The reason why we need an account proxy is that we don't want to have global
+ * state directly stored in the container.
+ *
+ * This proxy object avoids multiple invocations of the authentication manager
+ * which can happen if the current user is accessed in constructors. It also
+ * allows legacy code to change the current user where the user cannot be
+ * directly injected into dependent code.
+ */
+class AccountProxy implements AccountProxyInterface {
+
+  /**
+   * The current request.
+   *
+   * @var \Symfony\Component\HttpFoundation\Request
+   */
+  protected $request;
+
+  /**
+   * The authentication manager.
+   *
+   * @var \Drupal\Core\Authentication\AuthenticationManagerInterface
+   */
+  protected $authenticationManager;
+
+  /**
+   * The instantiated account.
+   *
+   * @var \Drupal\Core\Session\AccountInterface
+   */
+  protected $account;
+
+  /**
+   * Constructs a new AccountProxy.
+   *
+   * @param \Drupal\Core\Authentication\AuthenticationManagerInterface $authentication_manager
+   *   The authentication manager.
+   */
+  public function __construct(AuthenticationManagerInterface $authentication_manager) {
+    $this->authenticationManager = $authentication_manager;
+  }
+
+  /**
+   * Sets the current request.
+   *
+   * @param \Symfony\Component\HttpFoundation\Request $request
+   *   The current request.
+   */
+  public function setRequest(Request $request) {
+    $this->request = $request;
+    // Reset the current user to ensure that new calls will return the correct
+    // user based on the request.
+    $this->account = NULL;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setAccount(AccountInterface $account) {
+    // If the passed account is already proxyed, use the actual account instead
+    // to prevent loops.
+    if ($account instanceof static) {
+      $account = $account->getAccount();
+    }
+    $this->account = $account;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getAccount() {
+    if (!isset($this->account)) {
+      $this->setAccount($this->authenticationManager->authenticate($this->request));
+    }
+    return $this->account;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function id() {
+    return $this->getAccount()->id();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getRoles($exclude_locked_roles = FALSE) {
+    return $this->getAccount()->getRoles();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getHostname() {
+    return $this->getAccount()->getHostname();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function hasPermission($permission) {
+    return $this->getAccount()->hasPermission($permission);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getSessionId() {
+    return $this->getAccount()->getSessionId();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getSecureSessionId() {
+    return $this->getAccount()->getSecureSessionId();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getSessionData() {
+    return $this->getAccount()->getSessionData();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function isAuthenticated() {
+    return $this->getAccount()->isAuthenticated();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function isAnonymous() {
+    return $this->getAccount()->isAnonymous();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getPreferredLangcode($default = NULL) {
+    return $this->getAccount()->getPreferredLangcode($default);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getPreferredAdminLangcode($default = NULL) {
+    return $this->getAccount()->getPreferredAdminLangcode($default);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getUsername() {
+    return $this->getAccount()->getUsername();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getEmail() {
+    return $this->getAccount()->getEmail();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getTimeZone() {
+    return $this->getAccount()->getTimeZone();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getLastAccessedTime() {
+    return $this->getAccount()->getLastAccessedTime();
+  }
+
+}
+
diff --git a/core/lib/Drupal/Core/Session/AccountProxyInterface.php b/core/lib/Drupal/Core/Session/AccountProxyInterface.php
new file mode 100644
index 0000000..a415ea3
--- /dev/null
+++ b/core/lib/Drupal/Core/Session/AccountProxyInterface.php
@@ -0,0 +1,38 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Core\Session\AccountProxyInterface.
+ */
+
+namespace Drupal\Core\Session;
+
+/**
+ * Defines an interface for a service which has the current account stored.
+ */
+interface AccountProxyInterface extends AccountInterface {
+
+  /**
+   * Set the current wrapped account.
+   *
+   * Setting the current account is highly discouraged! Instead, make sure to
+   * inject the desired user object into the dependent code directly
+   *
+   * @param \Drupal\Core\Session\AccountInterface
+   *   The current account.
+   */
+  public function setAccount(AccountInterface $account);
+
+  /**
+   * Set the current wrapped account.
+   *
+   * Setting the current account is highly discouraged! Instead, make sure to
+   * inject the desired user object into the dependent code directly
+   *
+   * @param \Drupal\Core\Session\AccountInterface
+   *   The current account.
+   */
+  public function getAccount();
+
+}
+
diff --git a/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceSelectionAccessTest.php b/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceSelectionAccessTest.php
index 0178a25..19f5035 100644
--- a/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceSelectionAccessTest.php
+++ b/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceSelectionAccessTest.php
@@ -120,7 +120,7 @@ public function testNodeHandler() {
 
     // Test as a non-admin.
     $normal_user = $this->drupalCreateUser(array('access content'));
-    $this->container->set('current_user', $normal_user);
+    \Drupal::currentUser()->setAccount($normal_user);
     $referenceable_tests = array(
       array(
         'arguments' => array(
@@ -172,7 +172,7 @@ public function testNodeHandler() {
 
     // Test as an admin.
     $admin_user = $this->drupalCreateUser(array('access content', 'bypass node access'));
-    $this->container->set('current_user', $admin_user);
+    \Drupal::currentUser()->setAccount($admin_user);
     $referenceable_tests = array(
       array(
         'arguments' => array(
@@ -266,7 +266,7 @@ public function testUserHandler() {
     }
 
     // Test as a non-admin.
-    $this->container->set('current_user', $users['non_admin']);
+    \Drupal::currentUser()->setAccount($users['non_admin']);
     $referenceable_tests = array(
       array(
         'arguments' => array(
@@ -305,7 +305,7 @@ public function testUserHandler() {
     );
     $this->assertReferenceable($instance, $referenceable_tests, 'User handler');
 
-    $this->container->set('current_user', $users['admin']);
+    \Drupal::currentUser()->setAccount($users['admin']);
     $referenceable_tests = array(
       array(
         'arguments' => array(
@@ -447,7 +447,7 @@ public function testCommentHandler() {
 
     // Test as a non-admin.
     $normal_user = $this->drupalCreateUser(array('access content', 'access comments'));
-    $this->container->set('current_user', $normal_user);
+    \Drupal::currentUser()->setAccount($normal_user);
     $referenceable_tests = array(
       array(
         'arguments' => array(
@@ -486,7 +486,7 @@ public function testCommentHandler() {
 
     // Test as a comment admin.
     $admin_user = $this->drupalCreateUser(array('access content', 'access comments', 'administer comments'));
-    $this->container->set('current_user', $admin_user);
+    \Drupal::currentUser()->setAccount($admin_user);
     $referenceable_tests = array(
       array(
         'arguments' => array(
@@ -504,7 +504,7 @@ public function testCommentHandler() {
 
     // Test as a node and comment admin.
     $admin_user = $this->drupalCreateUser(array('access content', 'access comments', 'administer comments', 'bypass node access'));
-    $this->container->set('current_user', $admin_user);
+    \Drupal::currentUser()->setAccount($admin_user);
     $referenceable_tests = array(
       array(
         'arguments' => array(
diff --git a/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceSelectionSortTest.php b/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceSelectionSortTest.php
index fbd4461..06f0a69 100644
--- a/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceSelectionSortTest.php
+++ b/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceSelectionSortTest.php
@@ -120,7 +120,7 @@ public function testSort() {
 
     // Test as a non-admin.
     $normal_user = $this->drupalCreateUser(array('access content'));
-    $this->container->set('current_user', $normal_user);
+    \Drupal::currentUser()->setAccount($normal_user);
 
     $handler = $this->container->get('plugin.manager.entity_reference.selection')->getSelectionHandler($instance);
 
diff --git a/core/modules/file/lib/Drupal/file/Tests/FileManagedUnitTestBase.php b/core/modules/file/lib/Drupal/file/Tests/FileManagedUnitTestBase.php
index 324b1b5..c9ec86d 100644
--- a/core/modules/file/lib/Drupal/file/Tests/FileManagedUnitTestBase.php
+++ b/core/modules/file/lib/Drupal/file/Tests/FileManagedUnitTestBase.php
@@ -37,7 +37,7 @@ function setUp() {
     $user = entity_create('user', array('uid' => 1, 'name' => $this->randomName()));
     $user->enforceIsNew();
     $user->save();
-    $this->container->set('current_user', $user);
+    \Drupal::currentUser()->setAccount($user);
   }
 
   /**
diff --git a/core/modules/file/lib/Drupal/file/Tests/ValidatorTest.php b/core/modules/file/lib/Drupal/file/Tests/ValidatorTest.php
index f054602..398860c 100644
--- a/core/modules/file/lib/Drupal/file/Tests/ValidatorTest.php
+++ b/core/modules/file/lib/Drupal/file/Tests/ValidatorTest.php
@@ -133,7 +133,7 @@ function testFileValidateSize() {
     $user = entity_create('user', array('uid' => 2, 'name' => $this->randomName()));
     $user->enforceIsNew();
     $user->save();
-    $this->container->set('current_user', $user);
+    \Drupal::currentUser()->setAccount($user);
 
     // Create a file with a size of 1000 bytes, and quotas of only 1 byte.
     $file = entity_create('file', array('filesize' => 1000));
diff --git a/core/modules/filter/lib/Drupal/filter/Tests/FilterAPITest.php b/core/modules/filter/lib/Drupal/filter/Tests/FilterAPITest.php
index bfd6672..216545a 100644
--- a/core/modules/filter/lib/Drupal/filter/Tests/FilterAPITest.php
+++ b/core/modules/filter/lib/Drupal/filter/Tests/FilterAPITest.php
@@ -207,7 +207,7 @@ function testTypedDataAPI() {
 
     // Test with anonymous user.
     $user = new AnonymousUserSession();
-    $this->container->set('current_user', $user);
+    \Drupal::currentUser()->setAccount($user);
 
     $expected_available_options = array(
       'filtered_html' => 'Filtered HTML',
@@ -246,7 +246,7 @@ function testTypedDataAPI() {
     $this->assertFilterFormatViolation($violations, 'filtered_html');
 
     // Set user with access to 'filtered_html' format.
-    $this->container->set('current_user', $filtered_html_user);
+    \Drupal::currentUser()->setAccount($filtered_html_user);
     $violations = $data->validate();
     $this->assertEqual(count($violations), 0, "No validation violation for accessible format 'filtered_html' found.");
 
diff --git a/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
index 065d4c8..9e702c4 100644
--- a/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/TestBase.php
@@ -18,6 +18,8 @@
 use Drupal\Core\Config\StorageInterface;
 use Drupal\Core\DrupalKernel;
 use Drupal\Core\Language\Language;
+use Drupal\Core\Session\AccountProxy;
+use Drupal\Core\Session\AnonymousUserSession;
 use Drupal\Core\StreamWrapper\PublicStream;
 use Drupal\Core\Utility\Error;
 use Symfony\Component\HttpFoundation\Request;
@@ -1087,7 +1089,7 @@ private function prepareEnvironment() {
 
     // Run all tests as a anonymous user by default, web tests will replace that
     // during the test set up.
-    $this->container->set('current_user', drupal_anonymous_user());
+    $this->container->set('current_user', new AnonymousUserSession());
 
     \Drupal::setContainer($this->container);
 
@@ -1146,7 +1148,7 @@ protected function rebuildContainer($environment = 'testing') {
     $this->container = \Drupal::getContainer();
     // The current user is set in TestBase::prepareEnvironment().
     $this->container->set('request', $request);
-    $this->container->set('current_user', \Drupal::currentUser());
+    $this->container->get('current_user')->setAccount(\Drupal::currentUser());
   }
 
   /**
diff --git a/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
index 3f86126..93db258 100644
--- a/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
@@ -681,7 +681,7 @@ protected function drupalLogin(AccountInterface $account) {
     $pass = $this->assert($this->drupalUserIsLoggedIn($account), format_string('User %name successfully logged in.', array('%name' => $account->getUsername())), 'User login');
     if ($pass) {
       $this->loggedInUser = $account;
-      $this->container->set('current_user', $account);
+      $this->container->get('current_user')->setAccount($account);
       // @todo Temporary workaround for not being able to use synchronized
       //   services in non dumped container.
       $this->container->get('access_subscriber')->setCurrentUser($account);
@@ -729,7 +729,7 @@ protected function drupalLogout() {
       // @see WebTestBase::drupalUserIsLoggedIn()
       unset($this->loggedInUser->session_id);
       $this->loggedInUser = FALSE;
-      $this->container->set('current_user', new AnonymousUserSession());
+      $this->container->get('current_user')->setAccount(new AnonymousUserSession());
     }
   }
 
diff --git a/core/modules/system/lib/Drupal/system/Tests/Entity/EntityAccessTest.php b/core/modules/system/lib/Drupal/system/Tests/Entity/EntityAccessTest.php
index ee64237..296b32f 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Entity/EntityAccessTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Entity/EntityAccessTest.php
@@ -49,8 +49,7 @@ function assertEntityAccess($ops, AccessibleInterface $object, AccountInterface
    */
   function testEntityAccess() {
     // Set up a non-admin user that is allowed to view test entities.
-    global $user;
-    $user = $this->createUser(array('uid' => 2), array('view test entity'));
+    \Drupal::currentUser()->setAccount($this->createUser(array('uid' => 2), array('view test entity')));
     $entity = entity_create('entity_test', array(
       'name' => 'test',
     ));
@@ -78,8 +77,7 @@ function testEntityAccess() {
    */
   function testEntityAccessDefaultController() {
     // The implementation requires that the global user id can be loaded.
-    global $user;
-    $user = $this->createUser(array('uid' => 2));
+    \Drupal::currentUser()->setAccount($this->createUser(array('uid' => 2)));
 
     // Check that the default access controller is used for entities that don't
     // have a specific access controller defined.
@@ -101,8 +99,7 @@ function testEntityAccessDefaultController() {
   function testEntityTranslationAccess() {
 
     // Set up a non-admin user that is allowed to view test entity translations.
-    global $user;
-    $user = $this->createUser(array('uid' => 2), array('view test entity translations'));
+    \Drupal::currentUser()->setAccount($this->createUser(array('uid' => 2), array('view test entity translations')));
 
     // Create two test languages.
     foreach (array('foo', 'bar') as $langcode) {
diff --git a/core/modules/system/lib/Drupal/system/Tests/Form/FormCacheTest.php b/core/modules/system/lib/Drupal/system/Tests/Form/FormCacheTest.php
index 0e6d629..db904e3 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Form/FormCacheTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Form/FormCacheTest.php
@@ -46,7 +46,7 @@ public function setUp() {
    * Tests the form cache with a logged-in user.
    */
   function testCacheToken() {
-    $this->container->set('current_user', new UserSession(array('uid' => 1)));
+    \Drupal::currentUser()->setAccount(new UserSession(array('uid' => 1)));
     form_set_cache($this->form_build_id, $this->form, $this->form_state);
 
     $cached_form_state = form_state_defaults();
diff --git a/core/modules/system/lib/Drupal/system/Tests/Theme/FunctionsTest.php b/core/modules/system/lib/Drupal/system/Tests/Theme/FunctionsTest.php
index 586e1eb..7aa294c 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Theme/FunctionsTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Theme/FunctionsTest.php
@@ -243,7 +243,7 @@ function testLinks() {
     $this->assertThemeOutput('links', $variables, $expected);
 
     // Verify the data- attributes for setting the "active" class on links.
-    $this->container->set('current_user', new UserSession(array('uid' => 1)));
+    \Drupal::currentUser()->setAccount(new UserSession(array('uid' => 1)));
     $variables['set_active_class'] = TRUE;
     $expected_links = '';
     $expected_links .= '<ul id="somelinks">';
diff --git a/core/modules/system/tests/modules/router_test_directory/lib/Drupal/router_test/TestContent.php b/core/modules/system/tests/modules/router_test_directory/lib/Drupal/router_test/TestContent.php
index 57a1a85..6559c70 100644
--- a/core/modules/system/tests/modules/router_test_directory/lib/Drupal/router_test/TestContent.php
+++ b/core/modules/system/tests/modules/router_test_directory/lib/Drupal/router_test/TestContent.php
@@ -58,9 +58,9 @@ public function test11() {
   }
 
   public function testAccount(UserInterface $user) {
-    $current_user = $this->currentUser();
-    \Drupal::getContainer()->set('current_user', $user);
-    return $current_user->getUsername() . ':' . $user->getUsername();
+    $current_user_name = $this->currentUser()->getUsername();
+    $this->currentUser()->setAccount($user);
+    return $current_user_name . ':' . $user->getUsername();
   }
 
   /**
diff --git a/core/modules/system/tests/modules/session_test/lib/Drupal/session_test/EventSubscriber/SessionTestSubscriber.php b/core/modules/system/tests/modules/session_test/lib/Drupal/session_test/EventSubscriber/SessionTestSubscriber.php
index f27fe0d..55225ae 100644
--- a/core/modules/system/tests/modules/session_test/lib/Drupal/session_test/EventSubscriber/SessionTestSubscriber.php
+++ b/core/modules/system/tests/modules/session_test/lib/Drupal/session_test/EventSubscriber/SessionTestSubscriber.php
@@ -30,6 +30,11 @@ class SessionTestSubscriber implements EventSubscriberInterface {
    *   The Event to process.
    */
   public function onKernelRequestSessionTest(GetResponseEvent $event) {
+    // Trigger the authentication in the test to ensure that $_SESSION has the
+    // needed data.
+    // @todo: On the longrun the session will be lazy initialized, so we no
+    // longer have to force it here.
+    \Drupal::currentUser()->getAccount();
     $this->emptySession = intval(empty($_SESSION));
   }