Merge branch '3.4' into 4.3

* 3.4: (21 commits)
  [SecurityBundle] fix return type declarations
  [BrowserKit] fix return type declarations
  [PropertyInfo] fix return type declarations
  [Bridge/Doctrine] fix return type declarations
  [Form] fix return type declarations
  [Console] fix return type declarations
  [Intl] fix return type declarations
  [Templating] fix return type declarations
  [DomCrawler] fix return type declarations
  [Validator] fix return type declarations
  [Process] fix return type declarations
  [Workflow] fix return type declarations
  [Cache] fix return type declarations
  [Serializer] fix return type declarations
  [Translation] fix return type declarations
  [DI] fix return type declarations
  [Config] fix return type declarations
  [HttpKernel] Fix return type declarations
  [Security] Fix return type declarations
  [Routing] Fix return type declarations
  ...

Author: nicolas-grekas

DateFormatter/IntlDateFormatter.php

@@ -415,7 +415,7 @@ public function localtime($value, &$position = 0)
      *                         contain -1 otherwise it will contain the position at which parsing
      *                         ended. If $parse_pos > strlen($value), the parse fails immediately.
      *
-     * @return int Parsed value as a timestamp
+     * @return int|false Parsed value as a timestamp
      *
      * @see https://php.net/intldateformatter.parse
      *