Pass in default array

src/DependencyInjection/PcmIconExtension.php

@@ -25,7 +25,7 @@ class PcmIconExtension extends Extension
 
         $definition = $container->getDefinition('pcm_icon.icon_extension');
 
-        // $definition->addArgument($config['default']);
+        $definition->addArgument($config['default']);
         $definition->addArgument($config['directories']);
         $definition->addArgument($config['colours']);
     }