Merge branch '2.5' into 2.6

* 2.5:
  [2.3] [HttpFoundation] [MimeTypeGuesser]
  Removed dead code and various cleaning
  [Console] Make it clear that the second argument is not about command options.
  Added the '-' character for spaceless on tag start and end to be consistent for block, if, set and for nodes
  [Yaml] fixed parse shortcut Key after unindented collection.
  [Console] fixed #10531
  Make the container considered non-fresh if the environment parameters are changed

Conflicts:
	src/Symfony/Bridge/Twig/Resources/views/Form/form_div_layout.html.twig

Author: fabpot

Authentication/Provider/PreAuthenticatedAuthenticationProvider.php

@@ -59,11 +59,7 @@ public function authenticate(TokenInterface $token)
         if (!$user = $token->getUser()) {
             throw new BadCredentialsException('No pre-authenticated principal found in request.');
         }
-        /*
-        if (null === $token->getCredentials()) {
-            throw new BadCredentialsException('No pre-authenticated credentials found in request.');
-        }
-        */
+
         $user = $this->userProvider->loadUserByUsername($user);
 
         $this->userChecker->checkPostAuth($user);