diff --git a/core/tests/Drupal/Tests/BrowserTestBase.php b/core/tests/Drupal/Tests/BrowserTestBase.php
index 575d8c5e812064a5d6233a44fdf7cc84f84ad376..aa72a494d031bbe60b2a30731bfced9670511618 100644
--- a/core/tests/Drupal/Tests/BrowserTestBase.php
+++ b/core/tests/Drupal/Tests/BrowserTestBase.php
@@ -73,13 +73,6 @@ abstract class BrowserTestBase extends \PHPUnit_Framework_TestCase {
    */
   protected $databasePrefix;
 
-  /**
-   * The site directory of the original parent site.
-   *
-   * @var string
-   */
-  protected $originalSiteDirectory;
-
   /**
    * Time limit in seconds for the test.
    *
@@ -1027,7 +1020,7 @@ protected function prepareEnvironment() {
     $kernel->prepareLegacyRequest($request);
     $this->prepareDatabasePrefix();
 
-    $this->originalSiteDirectory = $kernel->findSitePath($request);
+    $this->originalSite = $kernel->findSitePath($request);
 
     // Create test directory ahead of installation so fatal errors and debug
     // information can be logged during installation process.