Merge branch '3.4' into 4.1

* 3.4:
  supports() must return a boolean
  fix the event subscriber code example

Author: javiereguiluz

security/guard_authentication.rst

@@ -475,7 +475,7 @@ are two possible fixes:
         public function supports(Request $request)
         {
     +         // if there is already an authenticated user (likely due to the session)
-    +         // then return null and skip authentication: there is no need.
+    +         // then return false and skip authentication: there is no need.
     +         if ($this->security->getUser()) {
     +             return false;
     +         }

session/locale_sticky_session.rst

@@ -171,50 +171,14 @@ event::
                 $this->session->set('_locale', $user->getLocale());
             }
         }
-    }
-
-Then register the listener:
-
-.. configuration-block::
-
-    .. code-block:: yaml
-
-        # config/services.yaml
-        services:
-            App\EventListener\UserLocaleListener:
-                tags:
-                    - { name: kernel.event_listener, event: security.interactive_login, method: onInteractiveLogin, priority: 15 }
-
-    .. code-block:: xml
-
-        <!-- config/services.xml -->
-        <?xml version="1.0" encoding="UTF-8" ?>
-        <container xmlns="http://symfony.com/schema/dic/services"
-            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-            xsi:schemaLocation="http://symfony.com/schema/dic/services
-                http://symfony.com/schema/dic/services/services-1.0.xsd">
-
-            <services>
-                <service id="App\EventListener\UserLocaleListener">
-                    <tag name="kernel.event_listener"
-                        event="security.interactive_login"
-                        method="onInteractiveLogin" priority=15 />
-                </service>
-            </services>
-        </container>
 
-    .. code-block:: php
-
-        // config/services.php
-        use AppBundle\EventListener\UserLocaleListener;
-        use Symfony\Component\DependencyInjection\Reference;
-
-        $container
-            ->register(UserLocaleListener::class)
-            ->addTag(
-                'kernel.event_listener',
-                array('event' => 'security.interactive_login', 'method' => 'onInteractiveLogin', 'priority' => 15)
+        public static function getSubscribedEvents()
+        {
+            return array(
+                SecurityEvents::INTERACTIVE_LOGIN => 'onInteractiveLogin',
             );
+        }
+    }
 
 .. caution::