Merge branch '2.8' into 3.4

* 2.8:
  improve docblocks around group sequences
  [WebProfilerBundle] added a note in the README
  [Filesystem] Skip tests on readable file when run with root user
  [FWBundle] Fix an error in WebTestCase::createClient's PHPDoc
  [HttpFoundation][Security] forward locale and format to subrequests
  [Console] Send the right exit code to console.terminate listeners
  Caching missed templates on cache warmup

Author: fabpot

Extension/Validator/Constraints/FormValidator.php

@@ -137,7 +137,7 @@ public function validate($form, Constraint $constraint)
     /**
      * Returns the validation groups of the given form.
      *
-     * @return array The validation groups
+     * @return string|GroupSequence|(string|GroupSequence)[] The validation groups
      */
     private static function getValidationGroups(FormInterface $form)
     {
@@ -172,10 +172,10 @@ private static function getValidationGroups(FormInterface $form)
     /**
      * Post-processes the validation groups option for a given form.
      *
-     * @param array|callable $groups The validation groups
-     * @param FormInterface  $form   The validated form
+     * @param string|GroupSequence|(string|GroupSequence)[]|callable $groups The validation groups
+     * @param FormInterface                                          $form   The validated form
      *
-     * @return array The validation groups
+     * @return (string|GroupSequence)[] The validation groups
      */
     private static function resolveValidationGroups($groups, FormInterface $form)
     {