[FrameworkBundle] Update deprecated service call

The service `security.context` is now deprecated due to PR #11690.

This commit updates PR #11593 replacing `security.context` with
`security.authorization_checker` in the `isGranted()` controller
shortcut.

src/Symfony/Bundle/FrameworkBundle/Controller/Controller.php

@@ -123,11 +123,11 @@ protected function addFlash($type, $message)
      */
     protected function isGranted($attributes, $object = null)
     {
-        if (!$this->container->has('security.context')) {
+        if (!$this->container->has('security.authorization_checker')) {
             throw new \LogicException('The SecurityBundle is not registered in your application.');
         }
 
-        return $this->container->get('security.context')->isGranted($attributes, $object);
+        return $this->container->get('security.authorization_checker')->isGranted($attributes, $object);
     }
 
     /**