Merge branch '2.8' into 3.3

* 2.8:
  [SecurityBundle] Fix syntax error in test
  [Console] Remove remaining dead code
  bumped Symfony version to 2.8.32
  bumped Symfony version to 2.7.39
  updated VERSION for 2.8.31
  updated CHANGELOG for 2.8.31
  updated VERSION for 2.7.38
  updated CHANGELOG for 2.7.38
  Replace array|\Traversable by iterable
  Fix ambiguous pattern

Author: nicolas-grekas

Constraints/UrlValidator.php

@@ -24,7 +24,7 @@ class UrlValidator extends ConstraintValidator
             (%s)://                                 # protocol
             (([\.\pL\pN-]+:)?([\.\pL\pN-]+)@)?      # basic auth
             (
-                ([\pL\pN\pS-\.])+(\.?([\pL\pN]|xn\-\-[\pL\pN-]+)+\.?) # a domain name
+                ([\pL\pN\pS\-\.])+(\.?([\pL\pN]|xn\-\-[\pL\pN-]+)+\.?) # a domain name
                     |                                                 # or
                 \d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}                    # an IP address
                     |                                                 # or

Validator/RecursiveContextualValidator.php

@@ -374,7 +374,7 @@ private function validateObject($object, $propertyPath, array $groups, $traversa
      * objects are iterated as well. Nested arrays are always iterated,
      * regardless of the value of $recursive.
      *
-     * @param array|\Traversable        $collection   The collection
+     * @param iterable                  $collection   The collection
      * @param string                    $propertyPath The current property path
      * @param string[]                  $groups       The validated groups
      * @param ExecutionContextInterface $context      The current execution context