Update to Drupal 8.0.0 beta 14. For more information, see https://drupal.org/node/2544542

core/modules/action/src/ActionFormBase.php

@@ -123,8 +123,8 @@ abstract class ActionFormBase extends EntityForm {
   /**
    * {@inheritdoc}
    */
-  public function validate(array $form, FormStateInterface $form_state) {
-    parent::validate($form, $form_state);
+  public function validateForm(array &$form, FormStateInterface $form_state) {
+    parent::validateForm($form, $form_state);
 
     if ($this->plugin instanceof PluginFormInterface) {
       $this->plugin->validateConfigurationForm($form, $form_state);

core/modules/action/src/Plugin/migrate/source/d6/Action.php

@@ -0,0 +1,58 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\action\Plugin\migrate\source\d6\Action.
+ */
+
+namespace Drupal\action\Plugin\migrate\source\d6;
+
+use Drupal\migrate_drupal\Plugin\migrate\source\DrupalSqlBase;
+
+/**
+ * Drupal 6 action source from database.
+ *
+ * @MigrateSource(
+ *   id = "d6_action"
+ * )
+ */
+class Action extends DrupalSqlBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function query() {
+    $query = $this->select('actions', 'a')
+      ->fields('a', array(
+        'aid',
+        'type',
+        'callback',
+        'parameters',
+        'description',
+      )
+    );
+    return $query;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function fields() {
+    return array(
+      'aid' => $this->t('Action ID'),
+      'type' => $this->t('Module'),
+      'callback' => $this->t('Callback function'),
+      'parameters' => $this->t('Action configuration'),
+      'description' => $this->t('Action description'),
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getIds() {
+    $ids['aid']['type'] = 'string';
+    return $ids;
+  }
+
+}

core/modules/action/src/Tests/Migrate/d6/MigrateActionConfigsTest.php

@@ -0,0 +1,47 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\action\Tests\Migrate\d6\MigrateActionConfigsTest.
+ */
+
+namespace Drupal\action\Tests\Migrate\d6;
+
+use Drupal\config\Tests\SchemaCheckTestTrait;
+use Drupal\migrate_drupal\Tests\d6\MigrateDrupal6TestBase;
+
+/**
+ * Upgrade variables to action.settings.yml.
+ *
+ * @group action
+ */
+class MigrateActionConfigsTest extends MigrateDrupal6TestBase {
+
+  use SchemaCheckTestTrait;
+
+  /**
+   * Modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = array('action');
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+    $this->loadDumps(['Variable.php']);
+    $this->executeMigration('d6_action_settings');
+  }
+
+  /**
+   * Tests migration of action variables to action.settings.yml.
+   */
+  public function testActionSettings() {
+    $config = $this->config('action.settings');
+    $this->assertIdentical(35, $config->get('recursion_limit'));
+    $this->assertConfigSchema(\Drupal::service('config.typed'), 'action.settings', $config->get());
+  }
+
+}