Use new request stack. Addresses #9.

src/Controller/AjaxBlocksController.php

@@ -11,7 +11,6 @@ use Drupal\Core\Render\RendererInterface;
 use Drupal\Core\Routing\CurrentRouteMatch;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\HttpFoundation\Request;
-use Symfony\Component\HttpFoundation\RequestStack;
 use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 use Symfony\Component\Routing\RouterInterface;
 
@@ -136,7 +135,7 @@ class AjaxBlocksController extends ControllerBase {
     }
 
     $new_request = Request::create($path);
-    $request_stack = new RequestStack();
+    $request_stack = \Drupal::requestStack();
     $processed = $this->pathProcessor->processInbound($new_request->getPathInfo(), $new_request);
 
     $this->currentPath->setPath($processed);

src/Form/AdvancedSearchForm.php

@@ -71,7 +71,7 @@ class AdvancedSearchForm extends FormBase {
    */
   public static function create(ContainerInterface $container) {
     return new static(
-      $container->get('request_stack')->getMasterRequest(),
+      $container->get('request_stack')->getMainRequest(),
       $container->get('current_route_match')
     );
   }

src/Plugin/Block/AdvancedSearchBlock.php

@@ -108,7 +108,7 @@ class AdvancedSearchBlock extends BlockBase implements ContainerFactoryPluginInt
       $plugin_definition,
       $container->get('plugin.manager.search_api.display'),
       $container->get('form_builder'),
-      $container->get('request_stack')->getMasterRequest()
+      $container->get('request_stack')->getMainRequest()
     );
   }
 

src/Plugin/Block/SearchResultsPagerBlock.php

@@ -58,7 +58,7 @@ class SearchResultsPagerBlock extends BlockBase implements ContainerFactoryPlugi
       $configuration,
       $plugin_id,
       $plugin_definition,
-      $container->get('request_stack')->getMasterRequest()
+      $container->get('request_stack')->getMainRequest()
     );
   }