fix sf4 deprecated using get() method for private container

Templating/TranslatableStringTwig.php

@@ -26,7 +26,22 @@ use Symfony\Component\DependencyInjection\ContainerAwareTrait;
 class TranslatableStringTwig extends \Twig_Extension
 {
     use ContainerAwareTrait;
-
+    
+    /**
+     * @var TranslatableStringHelper $helper
+     */
+    private $helper;
+    
+    /**
+     * TranslatableStringTwig constructor.
+     *
+     * @param TranslatableStringHelper $translatableStringHelper
+     */
+    public function __construct(TranslatableStringHelper $translatableStringHelper)
+    {
+        $this->helper = $translatableStringHelper;
+    }
+    
     /*
      * Returns a list of filters to add to the existing list.
      * 
@@ -42,7 +57,7 @@ class TranslatableStringTwig extends \Twig_Extension
     
     public function localize(array $translatableStrings)
     {
-        return $this->container->get('chill.main.helper.translatable_string')
+        return $this->helper
             ->localize($translatableStrings);
     }