diff --git a/core/modules/system/src/Tests/Common/AttachedAssetsTest.php b/core/modules/system/src/Tests/Common/AttachedAssetsTest.php
index ac7c47b..ea0280d 100644
--- a/core/modules/system/src/Tests/Common/AttachedAssetsTest.php
+++ b/core/modules/system/src/Tests/Common/AttachedAssetsTest.php
@@ -52,6 +52,8 @@ class AttachedAssetsTest extends KernelTestBase {
    */
   protected function setUp() {
     parent::setUp();
+    $this->installSchema('system', array('router'));
+    $this->container->get('router.builder')->rebuild();
 
     $this->assetResolver = $this->container->get('asset.resolver');
     $this->renderer = $this->container->get('renderer');