/**
  * {@inheritDoc}
  */
 public function getConfigTreeBuilder()
 {
     $treeBuilder = new TreeBuilder();
     $rootNode = $treeBuilder->root(self::ROOT_NODE);
     $this->facebookAdapterConfiguration->addFacebookAdapterSection($rootNode);
     $this->facebookApplicationConfiguration->addFacebookApplicationSection($rootNode);
     return $treeBuilder;
 }
 /**
  * @param \Symfony\Component\DependencyInjection\ContainerBuilder $container
  * @return void
  * @throws \Laelaps\Bundle\Facebook\Exception\InvalidFacebookConfigurationPrefix
  */
 public function prepend(ContainerBuilder $container)
 {
     $config = $this->getExtensionConfiguration($container);
     $stripped = $this->configurationSchema->stripFacebookAdapterConfiguration($config);
     foreach ($container->getExtensions() as $name => $extension) {
         if ($extension instanceof FacebookExtensionInterface) {
             if ($extension->getFacebookApplicationConfigurationOnly($container)) {
                 $container->prependExtensionConfig($name, $this->prefixFacebookConfiguration($stripped, $extension, $container));
             } else {
                 $container->prependExtensionConfig($name, $this->prefixFacebookConfiguration($config, $extension, $container));
             }
         }
     }
 }