diff --git a/core/modules/system/lib/Drupal/system/Tests/Form/FileInclusionTest.php b/core/modules/system/lib/Drupal/system/Tests/Form/FileInclusionTest.php
deleted file mode 100644
index 3698067..0000000
--- a/core/modules/system/lib/Drupal/system/Tests/Form/FileInclusionTest.php
+++ /dev/null
@@ -1,47 +0,0 @@
-<?php
-
-/**
- * @file
- * Definition of Drupal\system\Tests\Form\FileInclusionTest.
- */
-
-namespace Drupal\system\Tests\Form;
-
-use Drupal\simpletest\WebTestBase;
-
-/**
- * Tests form API file inclusion.
- */
-class FileInclusionTest extends WebTestBase {
-
-  /**
-   * Modules to enable.
-   *
-   * @var array
-   */
-  public static $modules = array('form_test');
-
-  public static function getInfo() {
-    return array(
-      'name' => 'Form API file inclusion',
-      'description' => 'Tests form API file inclusion.',
-      'group' => 'Form API',
-    );
-  }
-
-  /**
-   * Tests loading an include specified in hook_menu().
-   */
-  function testLoadMenuInclude() {
-    $this->drupalPostAjaxForm('form-test/load-include-menu', array(), array('op' => t('Save')), 'system/ajax', array(), array(), 'form-test-load-include-menu');
-    $this->assertText('Submit callback called.');
-  }
-
-  /**
-   * Tests loading a custom specified include.
-   */
-  function testLoadCustomInclude() {
-    $this->drupalPostForm('form-test/load-include-custom', array(), t('Save'));
-    $this->assertText('Submit callback called.');
-  }
-}
diff --git a/core/modules/system/tests/modules/form_test/form_test.file.inc b/core/modules/system/tests/modules/form_test/form_test.file.inc
deleted file mode 100644
index 28a8622..0000000
--- a/core/modules/system/tests/modules/form_test/form_test.file.inc
+++ /dev/null
@@ -1,50 +0,0 @@
-<?php
-
-/**
- * @file
- * An include file to test loading it with the form API.
- */
-
-/**
- * Form constructor for testing FAPI file inclusion of the file specified in
- * hook_menu().
- *
- * @deprecated Use \Drupal\form_test\testLoadIncludeMenu()
- */
-function form_test_load_include_menu($form, &$form_state) {
-  // Submit the form via Ajax. That way the FAPI has to care about including
-  // the file specified in hook_menu().
-  $ajax_wrapper_id = drupal_html_id('form-test-load-include-menu-ajax-wrapper');
-  $form['ajax_wrapper'] = array(
-    '#markup' => '<div id="' . $ajax_wrapper_id . '"></div>',
-  );
-  $form['button'] = array(
-    '#type' => 'submit',
-    '#value' => t('Save'),
-    '#submit' => array('form_test_load_include_submit'),
-    '#ajax' => array(
-      'wrapper' => $ajax_wrapper_id,
-      'method' => 'append',
-      'callback' => 'form_test_load_include_menu_ajax',
-    ),
-  );
-  return $form;
-}
-
-/**
- * Submit callback for the form API file inclusion test forms.
- */
-function form_test_load_include_submit($form, $form_state) {
-  drupal_set_message('Submit callback called.');
-}
-
-/**
- * Ajax callback for the file inclusion via menu test.
- */
-function form_test_load_include_menu_ajax($form) {
-  // We don't need to return anything, since #ajax['method'] is 'append', which
-  // does not remove the original #ajax['wrapper'] element, and status messages
-  // are automatically added by the Ajax framework as long as there's a wrapper
-  // element to add them to.
-  return '';
-}
diff --git a/core/modules/system/tests/modules/form_test/form_test.module b/core/modules/system/tests/modules/form_test/form_test.module
index 35a107b..7a753e1 100644
--- a/core/modules/system/tests/modules/form_test/form_test.module
+++ b/core/modules/system/tests/modules/form_test/form_test.module
@@ -1989,26 +1989,6 @@ function form_test_user_register_form_rebuild($form, &$form_state) {
   $form_state['rebuild'] = TRUE;
 }
 
-/**
- * Menu callback for testing custom form includes.
- *
- * @deprecated Use \Drupal\form_test\testLoadIncludeCustom()
- */
-function form_test_load_include_custom($form, &$form_state) {
-  $form['button'] = array(
-    '#type' => 'submit',
-    '#value' => t('Save'),
-    '#submit' => array('form_test_load_include_submit'),
-  );
-  // Specify the include file and enable form caching. That way the form is
-  // cached when it is submitted, but needs to find the specified submit handler
-  // in the include.
-  // Filename is a bit weird here: modules/system/tests/form_test.file.inc
-  form_load_include($form_state, 'inc', 'form_test', 'form_test.file');
-  $form_state['cache'] = TRUE;
-  return $form;
-}
-
 function form_test_checkbox_type_juggling($form, $form_state, $default_value, $return_value) {
   $form['checkbox'] = array(
     '#title' => t('Checkbox'),
diff --git a/core/modules/system/tests/modules/form_test/form_test.routing.yml b/core/modules/system/tests/modules/form_test/form_test.routing.yml
index 96d1bc7..0067dc5 100644
--- a/core/modules/system/tests/modules/form_test/form_test.routing.yml
+++ b/core/modules/system/tests/modules/form_test/form_test.routing.yml
@@ -166,7 +166,7 @@ form_test.tableselect_empty_text:
     _access: 'TRUE'
 
 form_test.tableselect_js:
-  path: '/form_test/tableselect/advanced-select'
+  path: '/form_test/tableselect/advanced-select/{test_action}'
   defaults:
     _content: '\Drupal\form_test\Form\FormTestForm::testTableSelectJS'
     _title: 'Tableselect js_select tests'
@@ -365,27 +365,12 @@ form_test.clicked_button:
   requirements:
     _access: 'TRUE'
 
-form_test.load_include_menu:
-  path: '/form-test/load-include-menu'
-  defaults:
-    _content: '\Drupal\form_test\Form\FormTestForm::testLoadIncludeMenu'
-    _title: 'FAPI test loading includes'
-  requirements:
-    _access: 'TRUE'
-
-form_test.load_include_custom:
-  path: '/form-test/load-include-custom'
-  defaults:
-    _content: '\Drupal\form_test\Form\FormTestForm::testLoadIncludeCustom'
-    _title: 'FAPI test loading includes'
-  requirements:
-    _access: 'TRUE'
-
 form_test.checkboxes_zero:
-  path: '/form-test/checkboxes-zero'
+  path: '/form-test/checkboxes-zero/{json}'
   defaults:
     _content: '\Drupal\form_test\Form\FormTestForm::testCheckboxesZero'
     _title: 'FAPI test involving checkboxes and zero'
+    json: TRUE
   requirements:
     _access: 'TRUE'
 
diff --git a/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/Form/FormTestForm.php b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/Form/FormTestForm.php
index 45cd9a2..ba1c7fb 100644
--- a/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/Form/FormTestForm.php
+++ b/core/modules/system/tests/modules/form_test/lib/Drupal/form_test/Form/FormTestForm.php
@@ -107,8 +107,8 @@ public function testTableSelectEmptyText() {
    *
    * @todo Remove _form_test_tableselect_js_select_form().
    */
-  public function testTableSelectJS() {
-    return drupal_get_form('_form_test_tableselect_js_select_form');
+  public function testTableSelectJS($test_action) {
+    return drupal_get_form('_form_test_tableselect_js_select_form', $test_action);
   }
 
   /**
@@ -162,7 +162,7 @@ public function testFormStateCleanAdvanced() {
    * @todo Remove _form_test_checkbox().
    */
   public function testCheckbox() {
-    return drupal_get_form('form_test_checkbox');
+    return drupal_get_form('_form_test_checkbox');
   }
 
   /**
@@ -252,7 +252,7 @@ public function testColor() {
    * @todo Remove form_test_checkboxes_radios().
    */
   public function testCheckboxesRadios() {
-    return drupal_get_form('form_test_checkboxes_radio');
+    return drupal_get_form('form_test_checkboxes_radios');
   }
 
   /**
@@ -337,31 +337,12 @@ public function testClickedButton() {
   }
 
   /**
-   * Wraps form_test_load_include_menu().
-   *
-   * @todo Remove form_test_load_include_menu().
-   */
-  public function testLoadIncludeMenu() {
-    module_load_include('file.inc', 'form_test');
-    return drupal_get_form('form_test_load_include_menu');
-  }
-
-  /**
-   * Wraps form_test_load_include_custom().
-   *
-   * @todo Remove form_test_load_include_custom().
-   */
-  public function testLoadIncludeCustom() {
-    return drupal_get_form('form_test_load_include_custom');
-  }
-
-  /**
    * Wraps form_test_checkboxes_zero().
    *
    * @todo Remove form_test_checkboxes_zero().
    */
-  public function testCheckboxesZero() {
-    return drupal_get_form('form_test_checkboxes_zero');
+  public function testCheckboxesZero($json) {
+    return drupal_get_form('form_test_checkboxes_zero', $json);
   }
 
   /**