Merge branch '3.4' into 4.1

* 3.4:
  [php_cs] disable fopen_flags
  [DI] fix error in dumped container
  [CS] Remove unused variables passed to closures
  [DI] fix dumping setters before their inlined instances
  [CS] Remove empty comment
  [CS] Enforces null type hint on last position in phpDocs
  [CS] Use combined assignment operators when possible
  Fix a typo in error messages
  Don't return early as this bypasses the auto exit feature
  [Console] Add missing null to input values allowed types
  [PHPUnitBridge] Fix microtime() format
  bumped Symfony version to 3.4.17
  updated VERSION for 3.4.16
  updated CHANGELOG for 3.4.16
  bumped Symfony version to 2.8.47
  update CONTRIBUTORS for 2.8.46
  updated VERSION for 2.8.46
  updated CHANGELOG for 2.8.46

Author: nicolas-grekas

ValidatorBuilder.php

@@ -68,7 +68,7 @@ class ValidatorBuilder implements ValidatorBuilderInterface
     private $translator;
 
     /**
-     * @var null|string
+     * @var string|null
      */
     private $translationDomain;