title: Symfony 4 authenticated user token lost
body: <p>I have an issue with a login. When I enter the user credentials and press login button it creates a user token and redirects to the main page but when the request gets main page user token doesn't exist... 
  Here is data from dev.log file</p>
  
  <pre><code>request.INFO: Matched route "login_check". {"route":"login_check","route_parameters":{"_route":"login_check","_controller":"App\\Controller\\Auth\\LoginController::login"},"request_uri":"http://localhost:8082/login","method":"POST"} []
  security.INFO: User has been authenticated successfully. {"username":"jac@jack.com"} []
  security.DEBUG: Fallback to the default authentication success handler. [] []
  security.DEBUG: Clearing remember-me cookie. {"name":"REMEMBERME"} []
  security.DEBUG: Remember-me was requested; setting cookie. [] []
  security.DEBUG: Stored the security token in the session. {"key":"_security_main"} []
  request.INFO: Matched route "main". {"route":"main","route_parameters":{"_route":"main","_controller":"App\\Controller\\MainController::index"},"request_uri":"http://localhost:8082/","method":"GET"} []
  security.DEBUG: Read existing security token from the session. {"key":"_security_main","token_class":"Symfony\\Component\\Security\\Core\\Authentication\\Token\\UsernamePasswordToken"} []
  security.WARNING: Username could not be found in the selected user provider. {"username":null,"provider":"App\\Security\\UserProvider"} []
  security.DEBUG: Remember-me cookie detected. [] []
  security.INFO: User for remember-me cookie not found. {"exception":"[object] (Symfony\\Component\\Security\\Core\\Exception\\UsernameNotFoundException(code: 0): Username \"jac@jack.com\" does not exist. at /opt/aicty/src/Security/UserProvider.php:52)"} []
  security.DEBUG: Clearing remember-me cookie. {"name":"REMEMBERME"} []
  security.INFO: Populated the TokenStorage with an anonymous Token. [] []
  security.DEBUG: Access denied, the user is not fully authenticated; redirecting to authentication entry point. {"exception":"[object] (Symfony\\Component\\Security\\Core\\Exception\\AccessDeniedException(code: 403): Access Denied. at /opt/aicty/vendor/symfony/security/Http/Firewall/AccessListener.php:68)"} []
  security.DEBUG: Calling Authentication entry point. [] []
  request.INFO: Matched route "show_login". {"route":"show_login","route_parameters":{"_route":"show_login","_controller":"App\\Controller\\Auth\\LoginController::showLogin"},"request_uri":"http://localhost:8082/login","method":"GET"} []
  security.INFO: Populated the TokenStorage with an anonymous Token. [] []
  request.INFO: Matched route "_wdt". {"route":"_wdt","route_parameters":{"_route":"_wdt","_controller":"web_profiler.controller.profiler::toolbarAction","token":"e96cb7"},"request_uri":"http://localhost:8082/_wdt/e96cb7","method":"GET"} []
  </code></pre>
  
  <p>And here is my security yaml conf. I took User class and UserProvider class from symfony documentation.</p>
  
  <pre><code>security:
      encoders:
          App\Entity\User:
              algorithm: bcrypt
              cost: 12
      providers:
          japi:
              id: App\Security\UserProvider
      firewalls:
          dev:
              pattern: ^/(_(profiler|wdt)|css|images|js)/
              security: false
          main:
              anonymous: ~
              provider: japi
              simple_form:
                  login_path: show_login
                  check_path: login_check
                  username_parameter: email
                  password_parameter: password
                  authenticator: App\Security\Authenticator
                  remember_me: true
                  provider: japi
  </code></pre>