Merge branch '2.8' into 3.4

* 2.8:
  [SecurityBundle] Backport test
  [Security] fix merge of 2.7 into 2.8 + add test case
  backport regression test from 3.4
  Fix misspelling variable
  [DI] minor: use a strict comparision in setDecoratedService
  Follow-on to #25825: Fix edge case in getParameterOption.
  keep the context when validating forms

Author: xabbuh

Definition.php

@@ -129,7 +129,7 @@ public function getFactory()
      */
     public function setDecoratedService($id, $renamedId = null, $priority = 0)
     {
-        if ($renamedId && $id == $renamedId) {
+        if ($renamedId && $id === $renamedId) {
             throw new InvalidArgumentException(sprintf('The decorated service inner name for "%s" must be different than the service name itself.', $id));
         }