diff --git a/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php b/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php
index 1db14a2..0bf60eb 100644
--- a/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php
+++ b/core/lib/Drupal/Core/Config/Entity/ConfigStorageController.php
@@ -83,7 +83,7 @@ class ConfigStorageController extends EntityStorageControllerBase {
    *   The entity type for which the instance is created.
    * @param array $entity_info
    *   An array of entity info for the entity type.
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory service.
    * @param \Drupal\Core\Config\StorageInterface $config_storage
    *   The config storage service.
diff --git a/core/lib/Drupal/Core/Extension/ThemeHandler.php b/core/lib/Drupal/Core/Extension/ThemeHandler.php
index 40e59cb..1d34691 100644
--- a/core/lib/Drupal/Core/Extension/ThemeHandler.php
+++ b/core/lib/Drupal/Core/Extension/ThemeHandler.php
@@ -9,7 +9,7 @@
 
 use Drupal\Component\Utility\String;
 use Drupal\Core\Cache\CacheBackendInterface;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Routing\RouteBuilder;
 use Drupal\Core\SystemListingInfo;
 
@@ -45,7 +45,7 @@ class ThemeHandler implements ThemeHandlerInterface {
   /**
    * The config factory to get the enabled themes.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
@@ -87,7 +87,7 @@ class ThemeHandler implements ThemeHandlerInterface {
   /**
    * Constructs a new ThemeHandler.
    *
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory to get the enabled themes.
    * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
    *   The module handler to fire themes_enabled/themes_disabled hooks.
@@ -100,7 +100,7 @@ class ThemeHandler implements ThemeHandlerInterface {
    * @param \Drupal\Core\SystemListingInfo $system_list_info
    *   (optional) The system listing info.
    */
-  public function __construct(ConfigFactory $config_factory, ModuleHandlerInterface $module_handler, CacheBackendInterface $cache_backend, InfoParserInterface $info_parser, RouteBuilder $route_builder = NULL, SystemListingInfo $system_list_info = NULL) {
+  public function __construct(ConfigFactoryInterface $config_factory, ModuleHandlerInterface $module_handler, CacheBackendInterface $cache_backend, InfoParserInterface $info_parser, RouteBuilder $route_builder = NULL, SystemListingInfo $system_list_info = NULL) {
     $this->configFactory = $config_factory;
     $this->moduleHandler = $module_handler;
     $this->cacheBackend = $cache_backend;
diff --git a/core/lib/Drupal/Core/Form/FormBase.php b/core/lib/Drupal/Core/Form/FormBase.php
index 3dfd81c..bb34f18 100644
--- a/core/lib/Drupal/Core/Form/FormBase.php
+++ b/core/lib/Drupal/Core/Form/FormBase.php
@@ -7,7 +7,7 @@
 
 namespace Drupal\Core\Form;
 
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\DependencyInjection\ContainerInjectionInterface;
 use Drupal\Core\DependencyInjection\DependencySerialization;
 use Drupal\Core\Routing\UrlGeneratorInterface;
@@ -44,7 +44,7 @@
   /**
    * The config factory.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
@@ -144,13 +144,13 @@ public function setTranslationManager(TranslationInterface $translation_manager)
   /**
    * Sets the config factory for this form.
    *
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory.
    *
    * @return self
    *   The form.
    */
-  public function setConfigFactory(ConfigFactory $config_factory) {
+  public function setConfigFactory(ConfigFactoryInterface $config_factory) {
     $this->configFactory = $config_factory;
     return $this;
   }
diff --git a/core/lib/Drupal/Core/ImageToolkit/ImageToolkitManager.php b/core/lib/Drupal/Core/ImageToolkit/ImageToolkitManager.php
index 43686ff..eceab87 100644
--- a/core/lib/Drupal/Core/ImageToolkit/ImageToolkitManager.php
+++ b/core/lib/Drupal/Core/ImageToolkit/ImageToolkitManager.php
@@ -8,7 +8,7 @@
 namespace Drupal\Core\ImageToolkit;
 
 use Drupal\Core\Cache\CacheBackendInterface;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Language\LanguageManager;
 use Drupal\Core\Plugin\DefaultPluginManager;
 
@@ -20,7 +20,7 @@ class ImageToolkitManager extends DefaultPluginManager {
   /**
    * The config factory.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
@@ -34,10 +34,10 @@ class ImageToolkitManager extends DefaultPluginManager {
    *   Cache backend instance to use.
    * @param \Drupal\Core\Language\LanguageManager $language_manager
    *   The language manager.
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory.
    */
-  public function __construct(\Traversable $namespaces, CacheBackendInterface $cache_backend, LanguageManager $language_manager, ConfigFactory $config_factory) {
+  public function __construct(\Traversable $namespaces, CacheBackendInterface $cache_backend, LanguageManager $language_manager, ConfigFactoryInterface $config_factory) {
     parent::__construct('Plugin/ImageToolkit', $namespaces, 'Drupal\Core\ImageToolkit\Annotation\ImageToolkit');
 
     $this->setCacheBackend($cache_backend, $language_manager, 'image_toolkit_plugins');
diff --git a/core/lib/Drupal/Core/Mail/MailFactory.php b/core/lib/Drupal/Core/Mail/MailFactory.php
index d6bef9f..b69dc21 100644
--- a/core/lib/Drupal/Core/Mail/MailFactory.php
+++ b/core/lib/Drupal/Core/Mail/MailFactory.php
@@ -7,7 +7,7 @@
 
 namespace Drupal\Core\Mail;
 
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Component\Utility\String;
 
 /**
@@ -18,7 +18,7 @@ class MailFactory {
   /**
    * Config object for mail system configurations.
    *
-   * @var \Drupal\Core\Config\Config
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $mailConfig;
 
@@ -30,12 +30,12 @@ class MailFactory {
   protected $instances = array();
 
   /**
-   * Constructs a MailFActory object.
+   * Constructs a MailFactory object.
    *
-   * @param \Drupal\Core\Config\ConfigFactory $configFactory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $configFactory
    *   The configuration factory.
    */
-  public function __construct(ConfigFactory $configFactory) {
+  public function __construct(ConfigFactoryInterface $configFactory) {
     $this->mailConfig = $configFactory->get('system.mail');
   }
 
diff --git a/core/modules/aggregator/lib/Drupal/aggregator/Plugin/aggregator/processor/DefaultProcessor.php b/core/modules/aggregator/lib/Drupal/aggregator/Plugin/aggregator/processor/DefaultProcessor.php
index 85b7217..e589031 100644
--- a/core/modules/aggregator/lib/Drupal/aggregator/Plugin/aggregator/processor/DefaultProcessor.php
+++ b/core/modules/aggregator/lib/Drupal/aggregator/Plugin/aggregator/processor/DefaultProcessor.php
@@ -13,7 +13,7 @@
 use Drupal\aggregator\Entity\Feed;
 use Drupal\Core\Annotation\Translation;
 use Drupal\Core\Database\Database;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
@@ -33,7 +33,7 @@ class DefaultProcessor extends AggregatorPluginSettingsBase implements Processor
   /**
    * Contains the configuration object factory.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
@@ -46,10 +46,10 @@ class DefaultProcessor extends AggregatorPluginSettingsBase implements Processor
    *   The plugin_id for the plugin instance.
    * @param array $plugin_definition
    *   The plugin implementation definition.
-   * @param \Drupal\Core\Config\ConfigFactory $config
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config
    *   The configuration factory object.
    */
-  public function __construct(array $configuration, $plugin_id, array $plugin_definition, ConfigFactory $config) {
+  public function __construct(array $configuration, $plugin_id, array $plugin_definition, ConfigFactoryInterface $config) {
     $this->configFactory = $config;
     // @todo Refactor aggregator plugins to ConfigEntity so merging
     //   the configuration here is not needed.
diff --git a/core/modules/aggregator/tests/modules/aggregator_test/lib/Drupal/aggregator_test/Plugin/aggregator/processor/TestProcessor.php b/core/modules/aggregator/tests/modules/aggregator_test/lib/Drupal/aggregator_test/Plugin/aggregator/processor/TestProcessor.php
index 04a5c5a..d77f59a 100644
--- a/core/modules/aggregator/tests/modules/aggregator_test/lib/Drupal/aggregator_test/Plugin/aggregator/processor/TestProcessor.php
+++ b/core/modules/aggregator/tests/modules/aggregator_test/lib/Drupal/aggregator_test/Plugin/aggregator/processor/TestProcessor.php
@@ -12,7 +12,7 @@
 use Drupal\aggregator\Entity\Feed;
 use Drupal\aggregator\Annotation\AggregatorProcessor;
 use Drupal\Core\Annotation\Translation;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
@@ -32,7 +32,7 @@ class TestProcessor extends AggregatorPluginSettingsBase implements ProcessorInt
   /**
    * Contains the configuration object factory.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
@@ -57,10 +57,10 @@ public static function create(ContainerInterface $container, array $configuratio
    *   The plugin_id for the plugin instance.
    * @param array $plugin_definition
    *   The plugin implementation definition.
-   * @param \Drupal\Core\Config\ConfigFactory $config
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config
    *   The configuration factory object.
    */
-  public function __construct(array $configuration, $plugin_id, array $plugin_definition, ConfigFactory $config) {
+  public function __construct(array $configuration, $plugin_id, array $plugin_definition, ConfigFactoryInterface $config) {
     $this->configFactory = $config;
     parent::__construct($configuration + $this->getConfiguration(), $plugin_id, $plugin_definition);
   }
diff --git a/core/modules/block/lib/Drupal/block/BlockFormController.php b/core/modules/block/lib/Drupal/block/BlockFormController.php
index 5965c21..5189a37 100644
--- a/core/modules/block/lib/Drupal/block/BlockFormController.php
+++ b/core/modules/block/lib/Drupal/block/BlockFormController.php
@@ -8,7 +8,7 @@
 namespace Drupal\block;
 
 use Drupal\Core\Cache\Cache;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Entity\EntityFormController;
 use Drupal\Core\Entity\EntityManagerInterface;
 use Drupal\Core\Entity\Query\QueryFactory;
@@ -52,7 +52,7 @@ class BlockFormController extends EntityFormController {
   /**
    * The config factory.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
@@ -65,10 +65,10 @@ class BlockFormController extends EntityFormController {
    *   The entity query factory.
    * @param \Drupal\Core\Language\LanguageManager $language_manager
    *   The language manager.
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory.
    */
-  public function __construct(EntityManagerInterface $entity_manager, QueryFactory $entity_query_factory, LanguageManager $language_manager, ConfigFactory $config_factory) {
+  public function __construct(EntityManagerInterface $entity_manager, QueryFactory $entity_query_factory, LanguageManager $language_manager, ConfigFactoryInterface $config_factory) {
     $this->storageController = $entity_manager->getStorageController('block');
     $this->entityQueryFactory = $entity_query_factory;
     $this->languageManager = $language_manager;
diff --git a/core/modules/block/lib/Drupal/block/Plugin/Derivative/ThemeLocalTask.php b/core/modules/block/lib/Drupal/block/Plugin/Derivative/ThemeLocalTask.php
index 77a2235..540cf7b 100644
--- a/core/modules/block/lib/Drupal/block/Plugin/Derivative/ThemeLocalTask.php
+++ b/core/modules/block/lib/Drupal/block/Plugin/Derivative/ThemeLocalTask.php
@@ -8,7 +8,7 @@
 namespace Drupal\block\Plugin\Derivative;
 
 use Drupal\Component\Plugin\Derivative\DerivativeBase;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Plugin\Discovery\ContainerDerivativeInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
@@ -20,17 +20,17 @@ class ThemeLocalTask extends DerivativeBase implements ContainerDerivativeInterf
   /**
    * Stores the theme settings config object.
    *
-   * @var \Drupal\Core\Config\Config
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $config;
 
   /**
    * Constructs a new ThemeLocalTask.
    *
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface ConfigFactoryInterface
    *   The config factory.
    */
-  public function __construct(ConfigFactory $config_factory) {
+  public function __construct(ConfigFactoryInterface $config_factory) {
     $this->config = $config_factory->get('system.theme');
   }
 
diff --git a/core/modules/block/tests/Drupal/block/Tests/BlockFormControllerTest.php b/core/modules/block/tests/Drupal/block/Tests/BlockFormControllerTest.php
index 69b0a1b..4f8a47c 100644
--- a/core/modules/block/tests/Drupal/block/Tests/BlockFormControllerTest.php
+++ b/core/modules/block/tests/Drupal/block/Tests/BlockFormControllerTest.php
@@ -70,7 +70,7 @@ public function testGetUniqueMachineName() {
       ->disableOriginalConstructor()
       ->getMock();
 
-    $config_factory = $this->getMockBuilder('Drupal\Core\Config\ConfigFactory')
+    $config_factory = $this->getMockBuilder('Drupal\Core\Config\ConfigFactoryInterface')
       ->disableOriginalConstructor()
       ->getMock();
 
diff --git a/core/modules/book/lib/Drupal/book/BookManager.php b/core/modules/book/lib/Drupal/book/BookManager.php
index 9b415a8..9f8522f 100644
--- a/core/modules/book/lib/Drupal/book/BookManager.php
+++ b/core/modules/book/lib/Drupal/book/BookManager.php
@@ -13,7 +13,7 @@
 use Drupal\Core\Language\Language;
 use Drupal\Core\Session\AccountInterface;
 use Drupal\Core\StringTranslation\TranslationInterface;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\node\NodeInterface;
 
 /**
@@ -45,7 +45,7 @@ class BookManager {
   /**
    * Config Factory Service Object.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
@@ -59,7 +59,7 @@ class BookManager {
   /**
    * Constructs a BookManager object.
    */
-  public function __construct(Connection $connection, EntityManagerInterface $entity_manager, TranslationInterface $translation, ConfigFactory $config_factory) {
+  public function __construct(Connection $connection, EntityManagerInterface $entity_manager, TranslationInterface $translation, ConfigFactoryInterface $config_factory) {
     $this->connection = $connection;
     $this->entityManager = $entity_manager;
     $this->translation =  $translation;
diff --git a/core/modules/config_translation/lib/Drupal/config_translation/ConfigEntityMapper.php b/core/modules/config_translation/lib/Drupal/config_translation/ConfigEntityMapper.php
index 44e0d7f..15a5049 100644
--- a/core/modules/config_translation/lib/Drupal/config_translation/ConfigEntityMapper.php
+++ b/core/modules/config_translation/lib/Drupal/config_translation/ConfigEntityMapper.php
@@ -8,7 +8,7 @@
 namespace Drupal\config_translation;
 
 use Drupal\Component\Utility\Unicode;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\EntityManager;
 use Drupal\Core\Routing\RouteProviderInterface;
@@ -59,7 +59,7 @@ class ConfigEntityMapper extends ConfigNamesMapper {
    *   An array of plugin information as documented in
    *   ConfigNamesMapper::__construct() with the following additional keys:
    *   - entity_type: The name of the entity type this mapper belongs to.
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The configuration factory.
    * @param \Drupal\locale\LocaleConfigManager $locale_config_manager
    *   The locale configuration manager.
@@ -72,7 +72,7 @@ class ConfigEntityMapper extends ConfigNamesMapper {
    * @param \Drupal\Core\Entity\EntityManager $entity_manager
    *   The entity manager.
    */
-  public function __construct($plugin_id, array $plugin_definition, ConfigFactory $config_factory, LocaleConfigManager $locale_config_manager, ConfigMapperManagerInterface $config_mapper_manager, RouteProviderInterface $route_provider, TranslationInterface $translation_manager, EntityManager $entity_manager) {
+  public function __construct($plugin_id, array $plugin_definition, ConfigFactoryInterface $config_factory, LocaleConfigManager $locale_config_manager, ConfigMapperManagerInterface $config_mapper_manager, RouteProviderInterface $route_provider, TranslationInterface $translation_manager, EntityManager $entity_manager) {
     parent::__construct($plugin_id, $plugin_definition, $config_factory, $locale_config_manager, $config_mapper_manager, $route_provider, $translation_manager);
     $this->setType($plugin_definition['entity_type']);
 
diff --git a/core/modules/config_translation/lib/Drupal/config_translation/ConfigNamesMapper.php b/core/modules/config_translation/lib/Drupal/config_translation/ConfigNamesMapper.php
index 2df7387..6398930 100644
--- a/core/modules/config_translation/lib/Drupal/config_translation/ConfigNamesMapper.php
+++ b/core/modules/config_translation/lib/Drupal/config_translation/ConfigNamesMapper.php
@@ -7,7 +7,7 @@
 
 namespace Drupal\config_translation;
 
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Language\Language;
 use Drupal\Core\Plugin\PluginBase;
 use Drupal\Core\Routing\RouteProviderInterface;
@@ -26,7 +26,7 @@ class ConfigNamesMapper extends PluginBase implements ConfigMapperInterface, Con
   /**
    * The configuration factory.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
@@ -73,7 +73,7 @@ class ConfigNamesMapper extends PluginBase implements ConfigMapperInterface, Con
    *     Defaults to 20.
    *   - list_controller: (optional) Class name for list controller used to
    *     generate lists of this type of configuration.
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The configuration factory.
    * @param \Drupal\locale\LocaleConfigManager $locale_config_manager
    *   The locale configuration manager.
@@ -88,7 +88,7 @@ class ConfigNamesMapper extends PluginBase implements ConfigMapperInterface, Con
    *   Throws an exception if the route specified by the 'base_route_name' in
    *   the plugin definition could not be found by the route provider.
    */
-  public function __construct($plugin_id, array $plugin_definition, ConfigFactory $config_factory, LocaleConfigManager $locale_config_manager, ConfigMapperManagerInterface $config_mapper_manager, RouteProviderInterface $route_provider, TranslationInterface $translation_manager) {
+  public function __construct($plugin_id, array $plugin_definition, ConfigFactoryInterface $config_factory, LocaleConfigManager $locale_config_manager, ConfigMapperManagerInterface $config_mapper_manager, RouteProviderInterface $route_provider, TranslationInterface $translation_manager) {
     $this->pluginId = $plugin_id;
     $this->pluginDefinition = $plugin_definition;
 
diff --git a/core/modules/config_translation/tests/Drupal/config_translation/Tests/ConfigNamesMapperTest.php b/core/modules/config_translation/tests/Drupal/config_translation/Tests/ConfigNamesMapperTest.php
index 3df6ac0..7746a22 100644
--- a/core/modules/config_translation/tests/Drupal/config_translation/Tests/ConfigNamesMapperTest.php
+++ b/core/modules/config_translation/tests/Drupal/config_translation/Tests/ConfigNamesMapperTest.php
@@ -8,7 +8,7 @@
 namespace Drupal\config_translation\Tests;
 
 use Drupal\config_translation\ConfigNamesMapper;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Language\Language;
 use Drupal\Tests\UnitTestCase;
 use Symfony\Component\Routing\Route;
@@ -646,10 +646,10 @@ public function setConfigNames(array $config_names) {
   /**
    * Sets the configuration factory.
    *
-   * @var \Drupal\Core\Config\ConfigFactory $config_factory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory to set.
    */
-  public function setConfigFactory(ConfigFactory $config_factory) {
+  public function setConfigFactory(ConfigFactoryInterface $config_factory) {
     $this->configFactory = $config_factory;
   }
 
diff --git a/core/modules/contact/lib/Drupal/contact/Access/ContactPageAccess.php b/core/modules/contact/lib/Drupal/contact/Access/ContactPageAccess.php
index 182cc1a..3df8129 100644
--- a/core/modules/contact/lib/Drupal/contact/Access/ContactPageAccess.php
+++ b/core/modules/contact/lib/Drupal/contact/Access/ContactPageAccess.php
@@ -8,7 +8,7 @@
 namespace Drupal\contact\Access;
 
 use Drupal\Core\Access\StaticAccessCheckInterface;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Session\AccountInterface;
 use Drupal\user\UserDataInterface;
 use Symfony\Component\Routing\Route;
@@ -22,7 +22,7 @@ class ContactPageAccess implements StaticAccessCheckInterface {
   /**
    * The contact settings config object.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
@@ -36,12 +36,12 @@ class ContactPageAccess implements StaticAccessCheckInterface {
   /**
    * Constructs a ContactPageAccess instance.
    *
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory.
    * @param \Drupal\user\UserDataInterface $user_data
    *   The user data service.
    */
-  public function __construct(ConfigFactory $config_factory, UserDataInterface $user_data) {
+  public function __construct(ConfigFactoryInterface $config_factory, UserDataInterface $user_data) {
     $this->configFactory = $config_factory;
     $this->userData = $user_data;
   }
diff --git a/core/modules/forum/lib/Drupal/forum/Form/Overview.php b/core/modules/forum/lib/Drupal/forum/Form/Overview.php
index 560d535..7947b3a 100644
--- a/core/modules/forum/lib/Drupal/forum/Form/Overview.php
+++ b/core/modules/forum/lib/Drupal/forum/Form/Overview.php
@@ -9,7 +9,6 @@
 
 use Drupal\Core\Entity\EntityManagerInterface;
 use Drupal\taxonomy\Form\OverviewTerms;
-use Drupal\Core\Config\ConfigFactory;
 use Drupal\Core\Extension\ModuleHandlerInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
diff --git a/core/modules/forum/lib/Drupal/forum/ForumManager.php b/core/modules/forum/lib/Drupal/forum/ForumManager.php
index 5c530c7..bcc7372 100644
--- a/core/modules/forum/lib/Drupal/forum/ForumManager.php
+++ b/core/modules/forum/lib/Drupal/forum/ForumManager.php
@@ -7,7 +7,7 @@
 
 namespace Drupal\forum;
 
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Database\Connection;
 use Drupal\Core\Entity\EntityManagerInterface;
 use Drupal\Core\StringTranslation\TranslationInterface;
@@ -43,7 +43,7 @@ class ForumManager implements ForumManagerInterface {
   /**
    * Forum settings config object.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
@@ -113,7 +113,7 @@ class ForumManager implements ForumManagerInterface {
   /**
    * Constructs the forum manager service.
    *
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory service.
    * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
    *   The entity manager service.
@@ -124,7 +124,7 @@ class ForumManager implements ForumManagerInterface {
    * @param \Drupal\Core\StringTranslation\TranslationInterface $translation_manager
    *   The translation manager service.
    */
-  public function __construct(ConfigFactory $config_factory, EntityManagerInterface $entity_manager, Connection $connection, FieldInfo $field_info, TranslationInterface $translation_manager) {
+  public function __construct(ConfigFactoryInterface $config_factory, EntityManagerInterface $entity_manager, Connection $connection, FieldInfo $field_info, TranslationInterface $translation_manager) {
     $this->configFactory = $config_factory;
     $this->entityManager = $entity_manager;
     $this->connection = $connection;
diff --git a/core/modules/forum/tests/Drupal/forum/Tests/ForumManagerTest.php b/core/modules/forum/tests/Drupal/forum/Tests/ForumManagerTest.php
index 8d3be5f..89f1460 100644
--- a/core/modules/forum/tests/Drupal/forum/Tests/ForumManagerTest.php
+++ b/core/modules/forum/tests/Drupal/forum/Tests/ForumManagerTest.php
@@ -34,7 +34,7 @@ public function testGetIndex() {
       ->disableOriginalConstructor()
       ->getMock();
 
-    $config_factory = $this->getMockBuilder('\Drupal\Core\Config\ConfigFactory')
+    $config_factory = $this->getMockBuilder('\Drupal\Core\Config\ConfigFactoryInterface')
       ->disableOriginalConstructor()
       ->getMock();
 
diff --git a/core/modules/language/lib/Drupal/language/Form/ContentLanguageSettingsForm.php b/core/modules/language/lib/Drupal/language/Form/ContentLanguageSettingsForm.php
index a253854..bd445dc 100644
--- a/core/modules/language/lib/Drupal/language/Form/ContentLanguageSettingsForm.php
+++ b/core/modules/language/lib/Drupal/language/Form/ContentLanguageSettingsForm.php
@@ -7,7 +7,7 @@
 
 namespace Drupal\language\Form;
 
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Config\Context\ContextInterface;
 use Drupal\Core\Entity\EntityManagerInterface;
 use Drupal\Core\Form\ConfigFormBase;
@@ -28,14 +28,14 @@ class ContentLanguageSettingsForm extends ConfigFormBase {
   /**
    * Constructs a ContentLanguageSettingsForm object.
    *
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory.
    * @param \Drupal\Core\Config\Context\ContextInterface $context
    *   The configuration context to use.
    * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
    *   The entity manager.
    */
-  public function __construct(ConfigFactory $config_factory, ContextInterface $context, EntityManagerInterface $entity_manager) {
+  public function __construct(ConfigFactoryInterface $config_factory, ContextInterface $context, EntityManagerInterface $entity_manager) {
     parent::__construct($config_factory, $context);
 
     $this->entityManager = $entity_manager;
diff --git a/core/modules/language/lib/Drupal/language/Form/NegotiationBrowserForm.php b/core/modules/language/lib/Drupal/language/Form/NegotiationBrowserForm.php
index 2271b14..a5c84ff 100644
--- a/core/modules/language/lib/Drupal/language/Form/NegotiationBrowserForm.php
+++ b/core/modules/language/lib/Drupal/language/Form/NegotiationBrowserForm.php
@@ -7,7 +7,7 @@
 
 namespace Drupal\language\Form;
 
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Config\Context\ContextInterface;
 use Drupal\Core\Extension\ModuleHandlerInterface;
 use Drupal\Core\Form\ConfigFormBase;
@@ -31,7 +31,7 @@ class NegotiationBrowserForm extends ConfigFormBase {
    * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
    *   The module handler
    */
-  public function __construct(ConfigFactory $config_factory, ContextInterface $context, ModuleHandlerInterface $module_handler) {
+  public function __construct(ConfigFactoryInterface $config_factory, ContextInterface $context, ModuleHandlerInterface $module_handler) {
     parent::__construct($config_factory, $context);
     $this->moduleHandler = $module_handler;
   }
diff --git a/core/modules/locale/lib/Drupal/locale/LocaleTranslation.php b/core/modules/locale/lib/Drupal/locale/LocaleTranslation.php
index b0983de..2c4590f 100644
--- a/core/modules/locale/lib/Drupal/locale/LocaleTranslation.php
+++ b/core/modules/locale/lib/Drupal/locale/LocaleTranslation.php
@@ -8,7 +8,7 @@
 namespace Drupal\locale;
 
 use Drupal\Core\Cache\CacheBackendInterface;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\DestructableInterface;
 use Drupal\Core\Language\Language;
 use Drupal\Core\Lock\LockBackendAbstract;
@@ -35,7 +35,7 @@ class LocaleTranslation implements TranslatorInterface, DestructableInterface {
   /**
    * The configuration factory.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
@@ -71,10 +71,10 @@ class LocaleTranslation implements TranslatorInterface, DestructableInterface {
    *   The cache backend.
    * @param \Drupal\Core\Lock\LockBackendInterface $lock
    *   The lock backend.
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory.
    */
-  public function __construct(StringStorageInterface $storage, CacheBackendInterface $cache, LockBackendInterface $lock, ConfigFactory $config_factory) {
+  public function __construct(StringStorageInterface $storage, CacheBackendInterface $cache, LockBackendInterface $lock, ConfigFactoryInterface $config_factory) {
     $this->storage = $storage;
     $this->cache = $cache;
     $this->lock = $lock;
diff --git a/core/modules/search/lib/Drupal/search/SearchPluginManager.php b/core/modules/search/lib/Drupal/search/SearchPluginManager.php
index dac919b..093fd8e 100644
--- a/core/modules/search/lib/Drupal/search/SearchPluginManager.php
+++ b/core/modules/search/lib/Drupal/search/SearchPluginManager.php
@@ -8,7 +8,7 @@
 namespace Drupal\search;
 
 use Drupal\Component\Utility\NestedArray;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Plugin\DefaultPluginManager;
 use Drupal\Core\Session\AccountInterface;
 use Drupal\Core\Cache\CacheBackendInterface;
@@ -22,14 +22,14 @@ class SearchPluginManager extends DefaultPluginManager {
   /**
    * The config factory.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
   /**
    * {@inheritdoc}
    */
-  public function __construct(\Traversable $namespaces, ConfigFactory $config_factory, CacheBackendInterface $cache_backend, LanguageManager $language_manager) {
+  public function __construct(\Traversable $namespaces, ConfigFactoryInterface $config_factory, CacheBackendInterface $cache_backend, LanguageManager $language_manager) {
     parent::__construct('Plugin/Search', $namespaces, 'Drupal\search\Annotation\SearchPlugin');
 
     $this->configFactory = $config_factory;
diff --git a/core/modules/system/lib/Drupal/system/Form/SiteMaintenanceModeForm.php b/core/modules/system/lib/Drupal/system/Form/SiteMaintenanceModeForm.php
index 693dc28..73170c6 100644
--- a/core/modules/system/lib/Drupal/system/Form/SiteMaintenanceModeForm.php
+++ b/core/modules/system/lib/Drupal/system/Form/SiteMaintenanceModeForm.php
@@ -7,7 +7,7 @@
 
 namespace Drupal\system\Form;
 
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Config\Context\ContextInterface;
 use Drupal\Core\KeyValueStore\StateInterface;
 use Drupal\Core\Form\ConfigFormBase;
@@ -28,14 +28,14 @@ class SiteMaintenanceModeForm extends ConfigFormBase {
   /**
    * Constructs a new SiteMaintenanceModeForm.
    *
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The factory for configuration objects.
    * @param \Drupal\Core\Config\Context\ContextInterface $context
    *   The configuration context to use.
    * @param \Drupal\Core\KeyValueStore\StateInterface $state
    *   The state keyvalue collection to use.
    */
-  public function __construct(ConfigFactory $config_factory, ContextInterface $context, StateInterface $state) {
+  public function __construct(ConfigFactoryInterface $config_factory, ContextInterface $context, StateInterface $state) {
     parent::__construct($config_factory, $context);
     $this->state = $state;
   }
diff --git a/core/modules/system/lib/Drupal/system/PathBasedBreadcrumbBuilder.php b/core/modules/system/lib/Drupal/system/PathBasedBreadcrumbBuilder.php
index 1f59256..050b341 100644
--- a/core/modules/system/lib/Drupal/system/PathBasedBreadcrumbBuilder.php
+++ b/core/modules/system/lib/Drupal/system/PathBasedBreadcrumbBuilder.php
@@ -8,7 +8,7 @@
 namespace Drupal\system;
 
 use Drupal\Core\Breadcrumb\BreadcrumbBuilderBase;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Controller\TitleResolverInterface;
 use Drupal\Core\Access\AccessManager;
 use Drupal\Core\Entity\EntityManagerInterface;
@@ -87,12 +87,12 @@ class PathBasedBreadcrumbBuilder extends BreadcrumbBuilderBase {
    *   The dynamic router service.
    * @param \Drupal\Core\PathProcessor\InboundPathProcessorInterface $path_processor
    *   The inbound path processor.
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory service.
    * @param \Drupal\Core\Controller\TitleResolverInterface $title_resolver
    *   The title resolver service.
    */
-  public function __construct(Request $request, EntityManagerInterface $entity_manager, AccessManager $access_manager, RequestMatcherInterface $router, InboundPathProcessorInterface $path_processor, ConfigFactory $config_factory, TitleResolverInterface $title_resolver) {
+  public function __construct(Request $request, EntityManagerInterface $entity_manager, AccessManager $access_manager, RequestMatcherInterface $router, InboundPathProcessorInterface $path_processor, ConfigFactoryInterface $config_factory, TitleResolverInterface $title_resolver) {
     $this->request = $request;
     $this->accessManager = $access_manager;
     $this->menuStorage = $entity_manager->getStorageController('menu');
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/TermFormController.php b/core/modules/taxonomy/lib/Drupal/taxonomy/TermFormController.php
index 925d83c..dfc4118 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/TermFormController.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/TermFormController.php
@@ -8,7 +8,7 @@
 namespace Drupal\taxonomy;
 
 use Drupal\Core\Cache\Cache;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Entity\ContentEntityFormController;
 use Drupal\Core\Entity\EntityManagerInterface;
 use Drupal\Core\Language\Language;
@@ -22,7 +22,7 @@ class TermFormController extends ContentEntityFormController {
   /**
    * The config factory.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
@@ -31,10 +31,10 @@ class TermFormController extends ContentEntityFormController {
    *
    * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
    *   The entity manager.
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory.
    */
-  public function __construct(EntityManagerInterface $entity_manager, ConfigFactory $config_factory) {
+  public function __construct(EntityManagerInterface $entity_manager, ConfigFactoryInterface $config_factory) {
     parent::__construct($entity_manager);
     $this->configFactory = $config_factory;
   }
diff --git a/core/modules/update/lib/Drupal/update/UpdateFetcher.php b/core/modules/update/lib/Drupal/update/UpdateFetcher.php
index 6893210..c8a5e90 100644
--- a/core/modules/update/lib/Drupal/update/UpdateFetcher.php
+++ b/core/modules/update/lib/Drupal/update/UpdateFetcher.php
@@ -7,7 +7,7 @@
 
 namespace Drupal\update;
 
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Guzzle\Http\ClientInterface;
 use Guzzle\Http\Exception\RequestException;
 
@@ -38,12 +38,12 @@ class UpdateFetcher {
   /**
    * Constructs a UpdateFetcher.
    *
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory.
    * @param \Guzzle\Http\ClientInterface $http_client
    *   A Guzzle client object.
    */
-  public function __construct(ConfigFactory $config_factory, ClientInterface $http_client) {
+  public function __construct(ConfigFactoryInterface $config_factory, ClientInterface $http_client) {
     $this->fetchUrl = $config_factory->get('update.settings')->get('fetch.url');
     $this->httpClient = $http_client;
   }
diff --git a/core/modules/user/lib/Drupal/user/Form/UserCancelForm.php b/core/modules/user/lib/Drupal/user/Form/UserCancelForm.php
index e1a3c6a..b9a0451 100644
--- a/core/modules/user/lib/Drupal/user/Form/UserCancelForm.php
+++ b/core/modules/user/lib/Drupal/user/Form/UserCancelForm.php
@@ -7,7 +7,7 @@
 
 namespace Drupal\user\Form;
 
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Entity\ContentEntityConfirmFormBase;
 use Drupal\Core\Entity\EntityManagerInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;
@@ -27,7 +27,7 @@ class UserCancelForm extends ContentEntityConfirmFormBase {
   /**
    * The config factory.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
@@ -41,12 +41,12 @@ class UserCancelForm extends ContentEntityConfirmFormBase {
   /**
    * Constructs an EntityFormController object.
    *
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory.
    * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
    *   The entity manager.
    */
-  public function __construct(EntityManagerInterface $entity_manager, ConfigFactory $config_factory) {
+  public function __construct(EntityManagerInterface $entity_manager, ConfigFactoryInterface $config_factory) {
     parent::__construct($entity_manager);
     $this->configFactory = $config_factory;
   }
diff --git a/core/modules/user/lib/Drupal/user/Form/UserMultipleCancelConfirm.php b/core/modules/user/lib/Drupal/user/Form/UserMultipleCancelConfirm.php
index ba85502..07295c5 100644
--- a/core/modules/user/lib/Drupal/user/Form/UserMultipleCancelConfirm.php
+++ b/core/modules/user/lib/Drupal/user/Form/UserMultipleCancelConfirm.php
@@ -8,7 +8,7 @@
 namespace Drupal\user\Form;
 
 use Drupal\Component\Utility\String;
-use Drupal\Core\Config\ConfigFactory;
+use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Entity\EntityManagerInterface;
 use Drupal\Core\Form\ConfirmFormBase;
 use Drupal\Core\Routing\UrlGeneratorInterface;
@@ -32,7 +32,7 @@ class UserMultipleCancelConfirm extends ConfirmFormBase {
   /**
    * The config factory.
    *
-   * @var \Drupal\Core\Config\ConfigFactory
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
    */
   protected $configFactory;
 
@@ -55,14 +55,14 @@ class UserMultipleCancelConfirm extends ConfirmFormBase {
    *
    * @param \Drupal\user\TempStoreFactory $temp_store_factory
    *   The temp store factory.
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory.
    * @param \Drupal\user\UserStorageControllerInterface $user_storage
    *   The user storage controller.
    * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
    *   The entity manager.
    */
-  public function __construct(TempStoreFactory $temp_store_factory, ConfigFactory $config_factory, UserStorageControllerInterface $user_storage, EntityManagerInterface $entity_manager) {
+  public function __construct(TempStoreFactory $temp_store_factory, ConfigFactoryInterface $config_factory, UserStorageControllerInterface $user_storage, EntityManagerInterface $entity_manager) {
     $this->tempStoreFactory = $temp_store_factory;
     $this->configFactory = $config_factory;
     $this->userStorage = $user_storage;
diff --git a/core/modules/user/lib/Drupal/user/UserAutocomplete.php b/core/modules/user/lib/Drupal/user/UserAutocomplete.php
index 4ffef4f..7c7dd05 100644
--- a/core/modules/user/lib/Drupal/user/UserAutocomplete.php
+++ b/core/modules/user/lib/Drupal/user/UserAutocomplete.php
@@ -35,7 +35,7 @@ class UserAutocomplete {
    *
    * @param \Drupal\Core\Database\Connection $connection
    *   The database connection to query for the user names.
-   * @param \Drupal\Core\Config\ConfigFactory $config_factory
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
    *   The config factory.
    */
   public function __construct(Connection $connection, ConfigFactoryInterface $config_factory) {