diff --git a/core/includes/common.inc b/core/includes/common.inc
index 1581de6..e05a1eb 100644
--- a/core/includes/common.inc
+++ b/core/includes/common.inc
@@ -3446,9 +3446,6 @@ function drupal_flush_all_caches() {
   // Reset all static caches.
   drupal_static_reset();
 
-  // Clear all non-drupal_static() static caches.
-  \Drupal::entityManager()->clearCachedDefinitions();
-
   // Wipe the PHP Storage caches.
   PhpStorageFactory::get('service_container')->deleteAll();
   PhpStorageFactory::get('twig')->deleteAll();
@@ -3498,6 +3495,9 @@ function drupal_flush_all_caches() {
   // Rebuild all information based on new module data.
   $module_handler->invokeAll('rebuild');
 
+  // Clear all plugin caches.
+  \Drupal::service('plugin.cache_clearer')->clearCachedDefinitions();
+
   // Rebuild the menu router based on all rebuilt data.
   // Important: This rebuild must happen last, so the menu router is guaranteed
   // to be based on up to date information.
diff --git a/core/modules/contextual/contextual.module b/core/modules/contextual/contextual.module
index 01b9aef..66550f2 100644
--- a/core/modules/contextual/contextual.module
+++ b/core/modules/contextual/contextual.module
@@ -86,30 +86,6 @@ function contextual_help($route_name, RouteMatchInterface $route_match) {
 }
 
 /**
- * Implements hook_element_info().
- *
- * @todo Remove once https://www.drupal.org/node/2326409 is in.
- */
-function contextual_element_info() {
-  $types['contextual_links_placeholder'] = array(
-    '#pre_render' => array('\Drupal\contextual\Element\ContextualLinksPlaceholder::preRenderPlaceholder'),
-    '#id' => NULL,
-  );
-  $types['contextual_links'] = array(
-    '#pre_render' => array('\Drupal\contextual\Element\ContextualLinks::preRenderLinks'),
-    '#theme' => 'links__contextual',
-    '#links' => array(),
-    '#attributes' => array('class' => array('contextual-links')),
-    '#attached' => array(
-      'library' => array(
-        'contextual/drupal.contextual-links',
-      ),
-    ),
-  );
-  return $types;
-}
-
-/**
  * Implements hook_preprocess().
  *
  * @see contextual_pre_render_placeholder()
diff --git a/core/modules/contextual/src/Element/ContextualLinks.php b/core/modules/contextual/src/Element/ContextualLinks.php
index 8aeec9f..180c01f 100644
--- a/core/modules/contextual/src/Element/ContextualLinks.php
+++ b/core/modules/contextual/src/Element/ContextualLinks.php
@@ -12,8 +12,7 @@
 /**
  * Provides a contextual_links element.
  *
- * @todo Annotate once https://www.drupal.org/node/2326409 is in.
- *   RenderElement("contextual_links")
+ * @RenderElement("contextual_links")
  */
 class ContextualLinks extends RenderElement {
 
diff --git a/core/modules/contextual/src/Element/ContextualLinksPlaceholder.php b/core/modules/contextual/src/Element/ContextualLinksPlaceholder.php
index ebe90fb..d10078b 100644
--- a/core/modules/contextual/src/Element/ContextualLinksPlaceholder.php
+++ b/core/modules/contextual/src/Element/ContextualLinksPlaceholder.php
@@ -13,8 +13,7 @@
 /**
  * Provides a contextual_links_placeholder element.
  *
- * @todo Annotate once https://www.drupal.org/node/2326409 is in.
- *   RenderElement("contextual_links_placeholder")
+ * @RenderElement("contextual_links_placeholder")
  */
 class ContextualLinksPlaceholder extends RenderElement {
 
diff --git a/core/modules/field_ui/field_ui.module b/core/modules/field_ui/field_ui.module
index e66da09..e8409e5 100644
--- a/core/modules/field_ui/field_ui.module
+++ b/core/modules/field_ui/field_ui.module
@@ -71,20 +71,6 @@ function field_ui_theme() {
 }
 
 /**
- * Implements hook_element_info().
- *
- * @todo Remove once https://www.drupal.org/node/2326409 is in.
- */
-function field_ui_element_info() {
-  return array(
-    'field_ui_table' => array(
-      '#theme' => 'field_ui_table',
-      '#regions' => array('' => array()),
-    ),
-  );
-}
-
-/**
  * Implements hook_entity_type_build().
  */
 function field_ui_entity_type_build(array &$entity_types) {
diff --git a/core/modules/field_ui/src/Element/FieldUiTable.php b/core/modules/field_ui/src/Element/FieldUiTable.php
index f34d6a4..361a17e 100644
--- a/core/modules/field_ui/src/Element/FieldUiTable.php
+++ b/core/modules/field_ui/src/Element/FieldUiTable.php
@@ -12,8 +12,7 @@
 /**
  * Provides a field_ui table element.
  *
- * @todo Annotate once https://www.drupal.org/node/2326409 is in.
- *   RenderElement("field_ui_table")
+ * @RenderElement("field_ui_table")
  */
 class FieldUiTable extends RenderElement {
 
diff --git a/core/modules/filter/filter.module b/core/modules/filter/filter.module
index cad200c..0cf6e42 100644
--- a/core/modules/filter/filter.module
+++ b/core/modules/filter/filter.module
@@ -87,34 +87,6 @@ function filter_theme() {
 }
 
 /**
- * Implements hook_element_info().
- *
- * @see filter_process_format()
- * @see text_format_wrapper()
- *
- * @todo Remove once https://www.drupal.org/node/2326409 is in.
- */
-function filter_element_info() {
-  $type['text_format'] = array(
-    '#process' => array(
-      '\Drupal\filter\Element\TextFormat::processFormat',
-    ),
-    '#base_type' => 'textarea',
-    '#theme_wrappers' => array('text_format_wrapper'),
-  );
-  $type['processed_text'] = array(
-    '#text' => '',
-    '#format' => NULL,
-    '#filter_types_to_skip' => array(),
-    '#langcode' => '',
-    '#pre_render' => array(
-      '\Drupal\filter\Element\ProcessedText::preRenderText',
-    ),
-  );
-  return $type;
-}
-
-/**
  * Retrieves a list of enabled text formats, ordered by weight.
  *
  * @param \Drupal\Core\Session\AccountInterface|null $account
diff --git a/core/modules/filter/src/Element/ProcessedText.php b/core/modules/filter/src/Element/ProcessedText.php
index 9ddbc55..b4a0eb0 100644
--- a/core/modules/filter/src/Element/ProcessedText.php
+++ b/core/modules/filter/src/Element/ProcessedText.php
@@ -16,8 +16,7 @@
 /**
  * Provides a processed text render element.
  *
- * @todo Annotate once https://www.drupal.org/node/2326409 is in.
- *   RenderElement("processed_text")
+ * @RenderElement("processed_text")
  */
 class ProcessedText extends RenderElement {
 
diff --git a/core/modules/filter/src/Element/TextFormat.php b/core/modules/filter/src/Element/TextFormat.php
index 72019fc..2716583 100644
--- a/core/modules/filter/src/Element/TextFormat.php
+++ b/core/modules/filter/src/Element/TextFormat.php
@@ -15,8 +15,7 @@
 /**
  * Provides a text format render element.
  *
- * @todo Annotate once https://www.drupal.org/node/2326409 is in.
- *   RenderElement("text_format")
+ * @enderElement("text_format")
  */
 class TextFormat extends RenderElement {
 
diff --git a/core/modules/language/language.module b/core/modules/language/language.module
index 40b9bfa..a83b3ec 100644
--- a/core/modules/language/language.module
+++ b/core/modules/language/language.module
@@ -170,22 +170,6 @@ function language_process_language_select($element) {
 }
 
 /**
- * Implements hook_element_info().
- *
- * @todo Remove once https://www.drupal.org/node/2326409 is in.
- */
-function language_element_info() {
-  $types['language_configuration'] = array(
-    '#input' => TRUE,
-    '#tree' => TRUE,
-    '#process' => array(
-      '\Drupal\language\Element\LanguageConfiguration::processLanguageConfiguration',
-    ),
-  );
-  return $types;
-}
-
-/**
  * Submit handler for the forms that have a language_configuration element.
  */
 function language_configuration_element_submit(&$form, FormStateInterface $form_state) {
diff --git a/core/modules/language/src/Element/LanguageConfiguration.php b/core/modules/language/src/Element/LanguageConfiguration.php
index e24f8bd..68cb46c 100644
--- a/core/modules/language/src/Element/LanguageConfiguration.php
+++ b/core/modules/language/src/Element/LanguageConfiguration.php
@@ -14,8 +14,7 @@
 /**
  * Provides language element configuration.
  *
- * @todo Annotate once https://www.drupal.org/node/2326409 is in.
- *   FormElement("language_configuration")
+ * @FormElement("language_configuration")
  */
 class LanguageConfiguration extends FormElement {
 
diff --git a/core/modules/toolbar/src/Element/Toolbar.php b/core/modules/toolbar/src/Element/Toolbar.php
index 700f5e2..1b682aa 100644
--- a/core/modules/toolbar/src/Element/Toolbar.php
+++ b/core/modules/toolbar/src/Element/Toolbar.php
@@ -12,8 +12,7 @@
 /**
  * Provides a render element for the default Drupal toolbar.
  *
- * @todo Annotate once https://www.drupal.org/node/2326409 is in.
- *   RenderElement("toolbar")
+ * @RenderElement("toolbar")
  */
 class Toolbar extends RenderElement {
 
diff --git a/core/modules/toolbar/src/Element/ToolbarItem.php b/core/modules/toolbar/src/Element/ToolbarItem.php
index 18ade46..0eeb5c4 100644
--- a/core/modules/toolbar/src/Element/ToolbarItem.php
+++ b/core/modules/toolbar/src/Element/ToolbarItem.php
@@ -15,8 +15,7 @@
  *
  * The 'tray' property contains a renderable array.
  *
- * @todo Annotate once https://www.drupal.org/node/2326409 is in.
- *   RenderElement("toolbar_item")
+ * @RenderElement("toolbar_item")
  */
 class ToolbarItem extends RenderElement {
 
diff --git a/core/modules/toolbar/toolbar.module b/core/modules/toolbar/toolbar.module
index 2fbf64d..6c777ce 100644
--- a/core/modules/toolbar/toolbar.module
+++ b/core/modules/toolbar/toolbar.module
@@ -48,59 +48,6 @@ function toolbar_theme($existing, $type, $theme, $path) {
 }
 
 /**
- * Implements hook_element_info().
- *
- * @todo Remove once https://www.drupal.org/node/2326409 is in.
- */
-function toolbar_element_info() {
-  $elements = array();
-
-  $elements['toolbar'] = array(
-    '#pre_render' => array(
-      '\Drupal\toolbar\Element\Toolbar::preRenderToolbar',
-    ),
-    '#theme' => 'toolbar',
-    '#attached' => array(
-      'library' => array(
-        'toolbar/toolbar',
-      ),
-    ),
-    // Metadata for the toolbar wrapping element.
-    '#attributes' => array(
-      // The id cannot be simply "toolbar" or it will clash with the simpletest
-      // tests listing which produces a checkbox with attribute id="toolbar"
-      'id' => 'toolbar-administration',
-      'role' => 'group',
-      'aria-label' => t('Site administration toolbar'),
-    ),
-    // Metadata for the administration bar.
-    '#bar' => array(
-      '#heading' => t('Toolbar items'),
-      '#attributes' => array(
-        'id' => 'toolbar-bar',
-        'role' => 'navigation',
-        'aria-label' => t('Toolbar items'),
-      ),
-    ),
-  );
-
-  // A toolbar item is wrapped in markup for common styling.  The 'tray'
-  // property contains a renderable array.
-  $elements['toolbar_item'] = array(
-    '#pre_render' => array(
-      '\Drupal\toolbar\Element\ToolbarItem::preRenderToolbarItem',
-    ),
-    '#theme' => 'toolbar_item',
-    'tab' => array(
-      '#type' => 'link',
-      '#title' => NULL,
-      '#href' => '',
-    ),
-  );
-  return $elements;
-}
-
-/**
  * Implements hook_page_build().
  *
  * Add admin toolbar to the page_top region automatically.
diff --git a/core/modules/views/src/Element/View.php b/core/modules/views/src/Element/View.php
index 611c95f..c9e084b 100644
--- a/core/modules/views/src/Element/View.php
+++ b/core/modules/views/src/Element/View.php
@@ -13,8 +13,7 @@
 /**
  * Provides a render element to display a view.
  *
- * @todo Annotate once https://www.drupal.org/node/2326409 is in.
- *   RenderElement("view")
+ * @RenderElement("view")
  */
 class View extends RenderElement {
 
diff --git a/core/modules/views/views.module b/core/modules/views/views.module
index 84b324f..360ab57 100644
--- a/core/modules/views/views.module
+++ b/core/modules/views/views.module
@@ -48,22 +48,6 @@ function views_help($route_name, RouteMatchInterface $route_match) {
 }
 
 /**
- * Implements hook_element_info().
- *
- * @todo Remove once https://www.drupal.org/node/2326409 is in.
- */
-function views_element_info() {
-  $types['view'] = array(
-    '#theme_wrappers' => array('container'),
-    '#pre_render' => array('\Drupal\views\Element\View::preRenderViewElement'),
-    '#name' => NULL,
-    '#display_id' => 'default',
-    '#arguments' => array(),
-  );
-  return $types;
-}
-
-/**
  * Implements hook_views_pre_render().
  */
 function views_views_pre_render($view) {