diff -u b/core/modules/config_translation/tests/src/Functional/ConfigTranslationViewListUiTest.php b/core/modules/config_translation/tests/src/Functional/ConfigTranslationViewListUiTest.php
--- b/core/modules/config_translation/tests/src/Functional/ConfigTranslationViewListUiTest.php
+++ b/core/modules/config_translation/tests/src/Functional/ConfigTranslationViewListUiTest.php
@@ -26,7 +26,7 @@
   public static $modules = ['config_translation', 'views_ui'];
 
   protected function setUp($import_test_views = TRUE) {
-    parent::setUp();
+    parent::setUp($import_test_views);
 
     $permissions = [
       'administer views',
diff -u b/core/modules/user/tests/src/Functional/AccessRoleUITest.php b/core/modules/user/tests/src/Functional/AccessRoleUITest.php
--- b/core/modules/user/tests/src/Functional/AccessRoleUITest.php
+++ b/core/modules/user/tests/src/Functional/AccessRoleUITest.php
@@ -31,7 +31,7 @@
    * {@inheritdoc}
    */
   protected function setUp($import_test_views = TRUE) {
-    parent::setUp();
+    parent::setUp($import_test_views);
 
     ViewTestData::createTestViews(get_class($this), ['user_test_views']);
   }
diff -u b/core/modules/views_ui/src/Tests/UITestBase.php b/core/modules/views_ui/src/Tests/UITestBase.php
--- b/core/modules/views_ui/src/Tests/UITestBase.php
+++ b/core/modules/views_ui/src/Tests/UITestBase.php
@@ -2,12 +2,15 @@
 
 namespace Drupal\views_ui\Tests;
 
-@trigger_error('\Drupal\views_ui\Tests\UITestBase is deprecated in Drupal 8.4.0 and will be removed before Drupal 9.0.0. Instead, use \Drupal\Tests\views_ui\Functional\UITestBase', E_USER_DEPRECATED);
+@trigger_error('\Drupal\views_ui\Tests\UITestBase is deprecated in Drupal 8.4.0 and will be removed before Drupal 9.0.x. Instead, use \Drupal\Tests\views_ui\Functional\UITestBase', E_USER_DEPRECATED);
 
 use Drupal\views\Tests\ViewTestBase;
 
 /**
  * Provides a base class for testing the Views UI.
+ *
+ * @deprecated in Drupal 8.4.0 and will be removed before Drupal 9.0.x.
+ *   Use \Drupal\Tests\views_ui\Functional\UITestBase.
  */
 abstract class UITestBase extends ViewTestBase {
 
diff -u b/core/modules/views_ui/tests/src/Functional/DisplayPathTest.php b/core/modules/views_ui/tests/src/Functional/DisplayPathTest.php
--- b/core/modules/views_ui/tests/src/Functional/DisplayPathTest.php
+++ b/core/modules/views_ui/tests/src/Functional/DisplayPathTest.php
@@ -16,7 +16,7 @@
   use AssertPageCacheContextsAndTagsTrait;
 
   protected function setUp($import_test_views = TRUE) {
-    parent::setUp();
+    parent::setUp($import_test_views);
 
     $this->placeBlock('page_title_block');
   }
diff -u b/core/modules/views_ui/tests/src/Functional/DuplicateTest.php b/core/modules/views_ui/tests/src/Functional/DuplicateTest.php
--- b/core/modules/views_ui/tests/src/Functional/DuplicateTest.php
+++ b/core/modules/views_ui/tests/src/Functional/DuplicateTest.php
@@ -10,7 +10,7 @@
 class DuplicateTest extends UITestBase {
 
   protected function setUp($import_test_views = TRUE) {
-    parent::setUp();
+    parent::setUp($import_test_views);
 
     $this->placeBlock('page_title_block');
   }
diff -u b/core/modules/views_ui/tests/src/Functional/FieldUITest.php b/core/modules/views_ui/tests/src/Functional/FieldUITest.php
--- b/core/modules/views_ui/tests/src/Functional/FieldUITest.php
+++ b/core/modules/views_ui/tests/src/Functional/FieldUITest.php
@@ -2,6 +2,7 @@
 
 namespace Drupal\Tests\views_ui\Functional;
 
+use Drupal\Component\Serialization\Json;
 use Drupal\views\Views;
 
 /**
@@ -69,10 +70,10 @@
     $this->assertLinkByHref($edit_groupby_url, 0, 'Aggregation link found.');
 
     // @todo Get this test working under BrowserTestBase.
-//    $edit_handler_url = '/admin/structure/views/ajax/handler-group/test_view/default/field/name';
-//    $this->drupalGet($edit_handler_url);
-//    $data = Json::decode($this->getRawContent());
-//    $this->assertEqual($data[3]['dialogOptions']['title'], 'Configure aggregation settings for field Views test: Name');
+    $edit_handler_url = '/admin/structure/views/ajax/handler-group/test_view/default/field/name';
+    $this->drupalGet($edit_handler_url);
+    $data = Json::decode($this->getSession()->getPage()->getContent());
+    $this->assertEqual($data[3]['dialogOptions']['title'], 'Configure aggregation settings for field Views test: Name');
   }
 
   /**
diff -u b/core/modules/views_ui/tests/src/Functional/HandlerTest.php b/core/modules/views_ui/tests/src/Functional/HandlerTest.php
--- b/core/modules/views_ui/tests/src/Functional/HandlerTest.php
+++ b/core/modules/views_ui/tests/src/Functional/HandlerTest.php
@@ -32,7 +32,7 @@
    * {@inheritdoc}
    */
   protected function setUp($import_test_views = TRUE) {
-    parent::setUp();
+    parent::setUp($import_test_views);
 
     $this->placeBlock('page_title_block');
     ViewTestData::createTestViews(get_class($this), ['node_test_views']);
diff -u b/core/modules/views_ui/tests/src/Functional/SettingsTest.php b/core/modules/views_ui/tests/src/Functional/SettingsTest.php
--- b/core/modules/views_ui/tests/src/Functional/SettingsTest.php
+++ b/core/modules/views_ui/tests/src/Functional/SettingsTest.php
@@ -20,7 +20,7 @@
    * {@inheritdoc}
    */
   protected function setUp($import_test_views = TRUE) {
-    parent::setUp();
+    parent::setUp($import_test_views);
     $this->drupalPlaceBlock('local_tasks_block');
   }
 
reverted:
--- b/core/modules/views_ui/tests/src/Functional/UITestBase.php
+++ /dev/null
@@ -1,90 +0,0 @@
-<?php
-
-namespace Drupal\Tests\views_ui\Functional;
-
-use Drupal\Tests\views\Functional\ViewTestBase;
-
-/**
- * Provides a base class for testing the Views UI.
- */
-abstract class UITestBase extends ViewTestBase {
-
-  /**
-   * An admin user with the 'administer views' permission.
-   *
-   * @var \Drupal\user\UserInterface
-   */
-  protected $adminUser;
-
-  /**
-   * An admin user with administrative permissions for views, blocks, and nodes.
-   *
-   * @var \Drupal\user\UserInterface
-   */
-  protected $fullAdminUser;
-
-  /**
-   * Modules to enable.
-   *
-   * @var array
-   */
-  public static $modules = ['node', 'views_ui', 'block', 'taxonomy'];
-
-  /**
-   * {@inheritdoc}
-   */
-  protected function setUp($import_test_views = TRUE) {
-    parent::setUp($import_test_views);
-
-    $this->enableViewsTestModule();
-
-    $this->adminUser = $this->drupalCreateUser(['administer views']);
-
-    $this->fullAdminUser = $this->drupalCreateUser(['administer views',
-      'administer blocks',
-      'bypass node access',
-      'access user profiles',
-      'view all revisions',
-      'administer permissions',
-    ]);
-    $this->drupalLogin($this->fullAdminUser);
-  }
-
-  /**
-   * A helper method which creates a random view.
-   */
-  public function randomView(array $view = []) {
-    // Create a new view in the UI.
-    $default = [];
-    $default['label'] = $this->randomMachineName(16);
-    $default['id'] = strtolower($this->randomMachineName(16));
-    $default['description'] = $this->randomMachineName(16);
-    $default['page[create]'] = TRUE;
-    $default['page[path]'] = $default['id'];
-
-    $view += $default;
-
-    $this->drupalPostForm('admin/structure/views/add', $view, t('Save and edit'));
-
-    return $default;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  protected function drupalGet($path, array $options = [], array $headers = []) {
-    $url = $this->buildUrl($path, $options);
-
-    // Ensure that each nojs page is accessible via ajax as well.
-    if (strpos($url, 'nojs') !== FALSE) {
-      $url = str_replace('nojs', 'ajax', $url);
-      $result = $this->drupalGet($url, $options);
-      $this->assertSession()->statusCodeEquals(200);
-      $this->assertEquals('application/json', $this->getSession()->getResponseHeader('Content-Type'));
-      $this->assertTrue(json_decode($result), 'Ensure that the AJAX request returned valid content.');
-    }
-
-    return parent::drupalGet($path, $options, $headers);
-  }
-
-}