diff -u b/core/modules/action/action.module b/core/modules/action/action.module
--- b/core/modules/action/action.module
+++ b/core/modules/action/action.module
@@ -52,7 +52,7 @@
     'link_title' => 'Actions',
     'description' => 'Manage the actions defined for your site.',
     'route_name' => 'action.admin',
-    'parent' => 'system.admin.config.system',
+    'parent' => 'system.admin_config_system',
   );
 
   return $links;
diff -u b/core/modules/ban/ban.module b/core/modules/ban/ban.module
--- b/core/modules/ban/ban.module
+++ b/core/modules/ban/ban.module
@@ -46,7 +46,7 @@
     'description' => 'Manage banned IP addresses.',
     'route_name' => 'ban.admin_page',
     'weight' => 10,
-    'parent' => 'user.admin.config.people',
+    'parent' => 'user.admin_index',
   );
 
   return $links;
diff -u b/core/modules/block/block.module b/core/modules/block/block.module
--- b/core/modules/block/block.module
+++ b/core/modules/block/block.module
@@ -98,7 +98,7 @@
 function block_menu_link_defaults() {
   $links['block.admin_display'] = array(
     'link_title' => 'Block layout',
-    'parent' => 'system.admin.structure',
+    'parent' => 'system.admin_structure',
     'description' => 'Configure what block content appears in your site\'s sidebars and other regions.',
     'route_name' => 'block.admin_display',
   );
diff -u b/core/modules/block/custom_block/custom_block.module b/core/modules/block/custom_block/custom_block.module
--- b/core/modules/block/custom_block/custom_block.module
+++ b/core/modules/block/custom_block/custom_block.module
@@ -38,24 +38,6 @@
 }
 
 /**
- * Implements hook_menu_link_defaults().
- */
-function custom_block_menu_link_defaults() {
-  $links['custom_block.add_page'] = array(
-    'link_title' => 'Add custom block',
-    'description' => 'Add custom block',
-    'route_name' => 'custom_block.add_page',
-  );
-  $items['custom_block.list'] = array(
-    'link_title' => 'Custom block library',
-    'parent' => 'block.admin_display',
-    'description' => 'Manage custom blocks.',
-  );
-
-  return $links;
-}
-
-/**
  * Implements hook_theme().
  */
 function custom_block_theme($existing, $type, $theme, $path) {
diff -u b/core/modules/book/book.module b/core/modules/book/book.module
--- b/core/modules/book/book.module
+++ b/core/modules/book/book.module
@@ -154,7 +154,7 @@
   $links['book.admin'] = array(
     'link_title' => 'Books',
     'description' => "Manage your site's book outlines.",
-    'parent' => 'system.admin.structure',
+    'parent' => 'system.admin_structure',
     'route_name' => 'book.admin',
   );
   $links['book.render'] = array(
diff -u b/core/modules/comment/comment.module b/core/modules/comment/comment.module
--- b/core/modules/comment/comment.module
+++ b/core/modules/comment/comment.module
@@ -171,13 +171,13 @@
   $links['comment.admin'] = array(
     'link_title' => 'Comments',
     'route_name' => 'comment.admin',
-    'parent' => \Drupal::moduleHandler()->moduleExists('node') ? 'node.content_overview' : 'system.admin',
+    'parent' => \Drupal::moduleHandler()->moduleExists('node') ? 'node.admin.content' : 'system.admin',
     'description' => 'List and edit site comments and the comment approval queue.',
   );
-  $links['comment.admin.structure.comments'] = array(
+  $links['comment.bundle_list'] = array(
     'link_title' => 'Comment forms',
     'route_name' => 'comment.bundle_list',
-    'parent' => 'system.admin.structure',
+    'parent' => 'system.admin_structure',
     'description' => 'Manage fields and displays settings for comment forms.',
   );
 
diff -u b/core/modules/config/config.module b/core/modules/config/config.module
--- b/core/modules/config/config.module
+++ b/core/modules/config/config.module
@@ -65,7 +65,7 @@
     'link_title' => 'Configuration management',
     'description' => 'Import, export, or synchronize your site configuration.',
     'route_name' => 'config.sync',
-    'parent' => 'system.admin.config.development',
+    'parent' => 'system.admin_config_development',
   );
 
   return $links;
diff -u b/core/modules/config_translation/config_translation.module b/core/modules/config_translation/config_translation.module
--- b/core/modules/config_translation/config_translation.module
+++ b/core/modules/config_translation/config_translation.module
@@ -37,7 +37,7 @@
 function config_translation_menu_link_defaults() {
   $links['config_translation.mapper_list'] = array(
     'link_title' => 'Configuration translation',
-    'parent' => 'system.admin.config.regional',
+    'parent' => 'system.admin_config_regional',
     'description' => 'Translate the configuration.',
     'route_name' => 'config_translation.mapper_list',
     'weight' => 30,
diff -u b/core/modules/contact/contact.module b/core/modules/contact/contact.module
--- b/core/modules/contact/contact.module
+++ b/core/modules/contact/contact.module
@@ -57,7 +57,7 @@
 function contact_menu_link_defaults() {
   $links['contact.category_list'] = array(
     'link_title' => 'Contact form categories',
-    'parent' => 'system.admin.structure',
+    'parent' => 'system.admin_structure',
     'description' => 'Create a system contact form and set up categories for the form to use.',
     'route_name' => 'contact.category_list',
   );
diff -u b/core/modules/dblog/dblog.module b/core/modules/dblog/dblog.module
--- b/core/modules/dblog/dblog.module
+++ b/core/modules/dblog/dblog.module
@@ -41,7 +41,7 @@
 function dblog_menu_link_defaults() {
   $links['dblog.overview'] = array(
     'link_title' => 'Recent log messages',
-    'parent' => 'system.admin.reports',
+    'parent' => 'system.admin_reports',
     'description' => 'View events that have recently been logged.',
     'route_name' => 'dblog.overview',
     'weight' => -1,
@@ -49,7 +49,7 @@
   $links['dblog.page_not_found'] = array(
     'link_title' => "Top 'page not found' errors",
     'route_name' => 'dblog.page_not_found',
-    'parent' => 'system.admin.reports',
+    'parent' => 'system.admin_reports',
     'description' => "View 'page not found' errors (404s).",
   );
   $links['dblog.access_denied'] = array(
@@ -64,7 +64,7 @@
       'link_title' => 'Top search phrases',
       'route_name' => 'dblog.search',
       'description' => 'View most popular search phrases.',
-      'parent' => 'system.admin.reports',
+      'parent' => 'system.admin_reports',
     );
   }
 
diff -u b/core/modules/entity/entity.module b/core/modules/entity/entity.module
--- b/core/modules/entity/entity.module
+++ b/core/modules/entity/entity.module
@@ -52,7 +52,7 @@
     'link_title' => 'Display modes',
     'description' => 'Configure what displays are available for your content and forms.',
     'route_name' => 'entity.display_mode',
-    'parent' => 'system.admin.structure',
+    'parent' => 'system.admin_structure',
   );
 
   // View modes.
diff -u b/core/modules/field_ui/field_ui.module b/core/modules/field_ui/field_ui.module
--- b/core/modules/field_ui/field_ui.module
+++ b/core/modules/field_ui/field_ui.module
@@ -60,7 +60,7 @@
     'link_title' => 'Field list',
     'description' => 'Overview of fields on all entity types.',
     'route_name' => 'field_ui.list',
-    'parent' => 'system.admin.reports',
+    'parent' => 'system.admin_reports',
   );
 
   return $links;
diff -u b/core/modules/filter/filter.module b/core/modules/filter/filter.module
--- b/core/modules/filter/filter.module
+++ b/core/modules/filter/filter.module
@@ -106,7 +106,7 @@
 
   $links['filter.admin_overview'] = array(
     'link_title' => 'Text formats',
-    'parent' => 'system.admin.config.content',
+    'parent' => 'system.admin_config_content',
     'description' => 'Configure how content input by users is filtered, including allowed HTML tags. Also allows enabling of module-provided filters.',
     'route_name' => 'filter.admin_overview',
   );
diff -u b/core/modules/forum/forum.module b/core/modules/forum/forum.module
--- b/core/modules/forum/forum.module
+++ b/core/modules/forum/forum.module
@@ -106,7 +106,7 @@
   );
   $links['forum.overview'] = array(
     'link_title' => 'Forums',
-    'parent' => 'system.admin.structure',
+    'parent' => 'system.admin_structure',
     'description' => 'Control forum hierarchy settings.',
     'route_name' => 'forum.overview',
   );
diff -u b/core/modules/image/image.module b/core/modules/image/image.module
--- b/core/modules/image/image.module
+++ b/core/modules/image/image.module
@@ -90,7 +90,7 @@
   $links['image.style_list'] = array(
     'link_title' => 'Image styles',
     'description' => 'Configure styles that can be used for resizing or adjusting images on display.',
-    'parent' => 'system.admin.config.media',
+    'parent' => 'system.admin_config_media',
     'route_name' => 'image.style_list',
   );
 
diff -u b/core/modules/language/language.module b/core/modules/language/language.module
--- b/core/modules/language/language.module
+++ b/core/modules/language/language.module
@@ -77,14 +77,14 @@
     'link_title' => 'Languages',
     'description' => 'Configure languages for content and the user interface.',
     'route_name' => 'language.admin_overview',
-    'parent' => 'system.admin.config.regional',
+    'parent' => 'system.admin_config_regional',
   );
   // Content language settings.
   $links['language.content_settings_page'] = array(
     'link_title' => 'Content language',
     'description' => 'Configure language support for content.',
     'route_name' => 'language.content_settings_page',
-    'parent' => 'system.admin.config.regional',
+    'parent' => 'system.admin_config_regional',
     'weight' => 10,
   );
 
diff -u b/core/modules/locale/locale.module b/core/modules/locale/locale.module
--- b/core/modules/locale/locale.module
+++ b/core/modules/locale/locale.module
@@ -176,7 +176,7 @@
     'link_title' => 'User interface translation',
     'description' => 'Translate the built-in user interface.',
     'route_name' => 'locale.translate_page',
-    'parent' => 'system.admin.config.regional',
+    'parent' => 'system.admin_config_regional',
     'weight' => 15,
   );
 
@@ -184,7 +184,7 @@
     'link_title' => 'Available translation updates',
     'route_name' => 'locale.translate_status',
     'description' => 'Get a status report about available interface translations for your installed modules and themes.',
-    'parent' => 'system.admin.reports',
+    'parent' => 'system.admin_reports',
   );
 
   return $links;
diff -u b/core/modules/menu/menu.module b/core/modules/menu/menu.module
--- b/core/modules/menu/menu.module
+++ b/core/modules/menu/menu.module
@@ -70,7 +70,7 @@
     'link_title' => 'Menus',
     'description' => 'Add new menus to your site, edit existing menus, and rename and reorganize menu links.',
     'route_name' => 'menu.overview_page',
-    'parent' => 'system.admin.structure',
+    'parent' => 'system.admin_structure',
   );
   return $links;
 }
diff -u b/core/modules/node/node.module b/core/modules/node/node.module
--- b/core/modules/node/node.module
+++ b/core/modules/node/node.module
@@ -950,7 +950,7 @@
 
   $links['node.overview_types'] = array(
     'link_title' => 'Content types',
-    'parent' => 'system.admin.structure',
+    'parent' => 'system.admin_structure',
     'description' => 'Manage content types, including default status, front page promotion, comment settings, etc.',
     'route_name' => 'node.overview_types',
   );
diff -u b/core/modules/path/path.module b/core/modules/path/path.module
--- b/core/modules/path/path.module
+++ b/core/modules/path/path.module
@@ -62,7 +62,7 @@
     'link_title' => 'URL aliases',
     'description' => "Change your site's URL paths by aliasing them.",
     'route_name' => 'path.admin_overview',
-    'parent' => 'system.admin.config.search',
+    'parent' => 'system.admin_config_search',
     'weight' => -5,
   );
 
diff -u b/core/modules/search/search.module b/core/modules/search/search.module
--- b/core/modules/search/search.module
+++ b/core/modules/search/search.module
@@ -149,7 +149,7 @@
   );
   $links['search.settings'] = array(
     'link_title' => 'Search settings',
-    'parent' => 'system.admin.config.search',
+    'parent' => 'system.admin_config_search',
     'description' => 'Configure relevance settings for search and other indexing options.',
     'route_name' => 'search.settings',
     'weight' => -10,
diff -u b/core/modules/shortcut/shortcut.module b/core/modules/shortcut/shortcut.module
--- b/core/modules/shortcut/shortcut.module
+++ b/core/modules/shortcut/shortcut.module
@@ -69,7 +69,7 @@
     'link_title' => 'Shortcuts',
     'description' => 'Add and modify shortcut sets.',
     'route_name' => 'shortcut.set_admin',
-    'parent' => 'system.admin.config.user-interface',
+    'parent' => 'system.admin_config_ui',
   );
 
   return $links;
diff -u b/core/modules/simpletest/simpletest.module b/core/modules/simpletest/simpletest.module
--- b/core/modules/simpletest/simpletest.module
+++ b/core/modules/simpletest/simpletest.module
@@ -42,7 +42,7 @@
     'link_title' => 'Testing',
     'description' => 'Run tests against Drupal core and your modules. These tests help assure that your site code is working as designed.',
     'route_name' => 'simpletest.test_form',
-    'parent' => 'system.admin.config.development',
+    'parent' => 'system.admin_config_development',
     'weight' => -5,
   );
 
diff -u b/core/modules/statistics/statistics.module b/core/modules/statistics/statistics.module
--- b/core/modules/statistics/statistics.module
+++ b/core/modules/statistics/statistics.module
@@ -86,7 +86,7 @@
     'link_title' => 'Statistics',
     'description' => 'Control details about what and how your site logs content statistics.',
     'route_name' => 'statistics.settings',
-    'parent' => 'system.admin.config.system',
+    'parent' => 'system.admin_config_system',
     'weight' => -15,
   );
   return $links;
diff -u b/core/modules/system/system.module b/core/modules/system/system.module
--- b/core/modules/system/system.module
+++ b/core/modules/system/system.module
@@ -653,7 +653,7 @@
  * Implements hook_menu_link_defaults().
  */
 function system_menu_link_defaults() {
-  $items['system.admin'] = array(
+  $links['system.admin'] = array(
     'link_title' => 'Administration',
     'route_name' => 'system.admin',
     'weight' => 9,
@@ -661,7 +661,7 @@
   );
 
   // Menu items that are basically just menu blocks.
-  $items['system.admin.structure'] = array(
+  $links['system.admin_structure'] = array(
     'route_name' => 'system.admin_structure',
     'parent' => 'system.admin',
     'description' => 'Administer blocks, content types, menus, etc.',
@@ -669,7 +669,7 @@
     'weight' => -8,
   );
   // Appearance.
-  $items['system.themes_page'] = array(
+  $links['system.themes_page'] = array(
     'route_name' => 'system.themes_page',
     'link_title' => 'Appearance',
     'description' => 'Select and configure your themes.',
@@ -677,7 +677,7 @@
     'weight' => -6,
   );
   // Modules.
-  $items['system.modules_list'] = array(
+  $links['system.modules_list'] = array(
     'link_title' => 'Extend',
     'description' => 'Add and enable modules to extend site functionality.',
     'parent' => 'system.admin',
@@ -685,7 +685,7 @@
     'weight' => -2,
   );
   // Configuration.
-  $items['system.admin_config'] = array(
+  $links['system.admin_config'] = array(
     'link_title' => 'Configuration',
     'parent' => 'system.admin',
     'description' => 'Administer settings.',
@@ -694,19 +694,19 @@
   );
 
   // Media settings.
-  $items['system.admin_config_media'] = array(
+  $links['system.admin_config_media'] = array(
     'route_name' => 'system.admin_config_media',
     'parent' => 'system.admin_config',
     'link_title' => 'Media',
     'weight' => -10,
   );
-  $items['system.file_system_settings'] = array(
+  $links['system.file_system_settings'] = array(
     'link_title' => 'File system',
     'description' => 'Tell Drupal where to store uploaded files and how they are accessed.',
     'parent' => 'system.admin_config_media',
     'route_name' => 'system.file_system_settings',
   );
-  $items['system.image_toolkit_settings'] = array(
+  $links['system.image_toolkit_settings'] = array(
     'link_title' => 'Image toolkit',
     'parent' => 'system.admin_config_media',
     'route_name' => 'system.image_toolkit_settings',
@@ -715,12 +715,12 @@
   );
 
   // Service settings.
-  $items['system.admin_config_services'] = array(
+  $links['system.admin_config_services'] = array(
     'link_title' => 'Web services',
     'parent' => 'system.admin_config',
     'route_name' => 'system.admin_config_services',
   );
-  $items['system.rss_feeds_settings'] = array(
+  $links['system.rss_feeds_settings'] = array(
     'link_title' => 'RSS publishing',
     'parent' => 'system.admin_config_services',
     'description' => 'Configure the site description, the number of items per feed and whether feeds should be titles/teasers/full-text.',
@@ -728,28 +728,28 @@
   );
 
   // Development settings.
-  $items['system.admin_config_development'] = array(
+  $links['system.admin_config_development'] = array(
     'route_name' => 'system.admin_config_development',
     'parent' => 'system.admin_config',
     'link_title' => 'Development',
     'description' => 'Development tools.',
     'weight' => -10,
   );
-  $items['system.admin.config.development.maintenance'] = array(
+  $links['system.site_maintenance_mode'] = array(
     'link_title' => 'Maintenance mode',
     'parent' => 'system.admin_config_development',
     'description' => 'Take the site offline for maintenance or bring it back online.',
     'route_name' => 'system.site_maintenance_mode',
     'weight' => -10,
   );
-  $items['system.performance_settings'] = array(
+  $links['system.performance_settings'] = array(
     'link_title' => 'Performance',
     'parent' => 'system.admin_config_development',
     'description' => 'Enable or disable page caching for anonymous users and set CSS and JS bandwidth optimization options.',
     'route_name' => 'system.performance_settings',
     'weight' => -20,
   );
-  $items['system.logging_settings'] = array(
+  $links['system.logging_settings'] = array(
     'link_title' => 'Logging and errors',
     'parent' => 'system.admin_config_development',
     'description' => "Settings for logging and alerts modules. Various modules can route Drupal's system events to different destinations, such as syslog, database, email, etc.",
@@ -758,21 +758,21 @@
   );
 
   // Regional and date settings.
-  $items['system.admin_config_regional'] = array(
+  $links['system.admin_config_regional'] = array(
     'route_name' => 'system.admin_config_regional',
     'link_title' => 'Regional and language',
     'parent' => 'system.admin_config',
     'description' => 'Regional settings, localization and translation.',
     'weight' => -5,
   );
-  $items['system.regional_settings'] = array(
+  $links['system.regional_settings'] = array(
     'link_title' => 'Regional settings',
     'parent' => 'system.admin_config_regional',
     'description' => "Settings for the site's default time zone and country.",
     'route_name' => 'system.regional_settings',
     'weight' => -20,
   );
-  $items['system.date_format_list'] = array(
+  $links['system.date_format_list'] = array(
     'link_title' => 'Date and time formats',
     'parent' => 'system.admin_config_regional',
     'description' => 'Configure display format strings for date and time.',
@@ -781,7 +781,7 @@
   );
 
   // Search settings.
-  $items['system.admin_config_search'] = array(
+  $links['system.admin_config_search'] = array(
     'link_title' => 'Search and metadata',
     'route_name' => 'system.admin_config_search',
     'parent' => 'system.admin_config',
@@ -790,21 +790,21 @@
   );
 
   // System settings.
-  $items['system.admin_config_system'] = array(
+  $links['system.admin_config_system'] = array(
     'link_title' => 'System',
     'route_name' => 'system.admin_config_system',
     'parent' => 'system.admin_config',
     'description' => 'General system related configuration.',
     'weight' => -20,
   );
-  $items['system.site_information_settings'] = array(
+  $links['system.site_information_settings'] = array(
     'link_title' => 'Site information',
     'parent' => 'system.admin_config_system',
     'description' => 'Change site name, e-mail address, slogan, default front page, and number of posts per page, error pages.',
     'route_name' => 'system.site_information_settings',
     'weight' => -20,
   );
-  $items['system.cron_settings'] = array(
+  $links['system.cron_settings'] = array(
     'link_title' => 'Cron',
     'parent' => 'system.admin_config_system',
     'description' => 'Manage automatic site maintenance tasks.',
@@ -812,21 +812,21 @@
     'weight' => 20,
   );
   // Additional categories
-  $items['system.admin_config_ui'] = array(
+  $links['system.admin_config_ui'] = array(
     'link_title' => 'User interface',
     'route_name' => 'system.admin_config_ui',
     'parent' => 'system.admin_config',
     'description' => 'Tools that enhance the user interface.',
     'weight' => -15,
   );
-  $items['system.admin_config_workflow'] = array(
+  $links['system.admin_config_workflow'] = array(
     'link_title' => 'Workflow',
     'route_name' => 'system.admin_config_workflow',
     'parent' => 'system.admin_config',
     'description' => 'Content workflow, editorial workflow tools.',
     'weight' => 5,
   );
-  $items['system.admin_config_content'] = array(
+  $links['system.admin_config_content'] = array(
     'link_title' => 'Content authoring',
     'route_name' => 'system.admin_config_content',
     'parent' => 'system.admin_config',
@@ -835,21 +835,21 @@
   );
 
   // Reports.
-  $items['system.admin_reports'] = array(
+  $links['system.admin_reports'] = array(
     'link_title' => 'Reports',
     'route_name' => 'system.admin_reports',
     'parent' => 'system.admin',
     'description' => 'View reports, updates, and errors.',
     'weight' => 5,
   );
-  $items['system.status'] = array(
+  $links['system.status'] = array(
     'link_title' => 'Status report',
     'parent' => 'system.admin_reports',
     'description' => "Get a status report about your site's operation and any detected problems.",
     'route_name' => 'system.status',
   );
 
-  return $items;
+  return $links;
 }
 
 /**
diff -u b/core/modules/user/user.module b/core/modules/user/user.module
--- b/core/modules/user/user.module
+++ b/core/modules/user/user.module
@@ -695,7 +695,7 @@
  */
 function user_menu_link_defaults() {
   // Registration and login pages.
-  $links['user'] = array(
+  $links['user.page'] = array(
     'link_title' => 'My account',
     'weight' => -10,
     'route_name' => 'user.page',
@@ -710,7 +710,7 @@
   );
 
   // User listing pages.
-  $links['user.admin.people'] = array(
+  $links['user.admin_account'] = array(
     'link_title' => 'People',
     'route_name' => 'user.admin_account',
     'description' => 'Manage user accounts, roles, and permissions.',
diff -u b/core/modules/views_ui/views_ui.module b/core/modules/views_ui/views_ui.module
--- b/core/modules/views_ui/views_ui.module
+++ b/core/modules/views_ui/views_ui.module
@@ -45,7 +45,7 @@
   $links = array();
 
   // Top-level Views module pages (not tied to a particular View).
-  $links['views_ui.admin.structure.views'] = array(
+  $links['views_ui.list'] = array(
     'link_title' => 'Views',
     'parent' => 'system.admin_structure',
     'description' => 'Manage customized lists of content.',
only in patch2:
unchanged:
--- a/core/modules/responsive_image/responsive_image.module
+++ b/core/modules/responsive_image/responsive_image.module
@@ -72,12 +72,12 @@ function responsive_image_menu() {
  * Implements hook_menu_link_defaults().
  */
 function responsive_image_menu_link_defaults() {
-  $links['responsive_image.admin.config.responsive_imagemapping'] = array(
+  $links['responsive_image.mapping_page'] = array(
     'link_title' => 'Responsive image mappings',
     'description' => 'Manage responsive image mappings',
     'weight' => 10,
     'route_name' => 'responsive_image.mapping_page',
-    'parent' => 'system.admin.config.media',
+    'parent' => 'system.admin_config_media',
   );
 
   return $links;
only in patch2:
unchanged:
--- a/core/modules/system/system.api.php
+++ b/core/modules/system/system.api.php
@@ -492,7 +492,7 @@ function hook_page_build(&$page) {
  * @see hook_menu_link_defaults_alter()
  */
 function hook_menu_link_defaults() {
-  $links['user'] = array(
+  $links['user.page'] = array(
     'link_title' => 'My account',
     'weight' => -10,
     'route_name' => 'user.page',
only in patch2:
unchanged:
--- a/core/modules/system/tests/modules/menu_test/menu_test.module
+++ b/core/modules/system/tests/modules/menu_test/menu_test.module
@@ -12,42 +12,42 @@
  */
 function menu_test_menu_link_defaults() {
   // The name of the menu changes during the course of the test. Using a $_GET.
-  $items['menu_test.menu_name_test'] = array(
+  $links['menu_test.menu_name_test'] = array(
     'link_title' => 'Test menu_name router item',
     'route_name' => 'menu_test.menu_name_test',
     'menu_name' => menu_test_menu_name(),
   );
   // This item uses SystemController::systemAdminMenuBlockPage() to list child
   // items.
-  $items['menu_test.menu_callback_description'] = array(
+  $links['menu_test.menu_callback_description'] = array(
     'link_title' => 'Menu item title',
     'description' => 'Menu item description parent',
     'route_name' => 'menu_test.callback_description',
   );
   // This item tests the description key.
-  $items['menu_test.menu_callback_description.description-plain'] = array(
+  $links['menu_test.menu_callback_description.description-plain'] = array(
     'link_title' => 'Menu item with a regular description',
     'description' => 'Menu item description text',
     'route_name' => 'menu_test.callback_description_plain',
     'parent' => 'menu_test.menu_callback_description',
   );
 
-  $items['menu_test.menu_no_title_callback'] = array(
+  $links['menu_test.menu_no_title_callback'] = array(
     'link_title' => 'A title with @placeholder',
     'route_name' => 'menu_test.menu_no_title_callback',
   );
 
   // Hierarchical tests.
-  $items['menu_test.hierarchy_parent'] = array(
+  $links['menu_test.hierarchy_parent'] = array(
     'link_title' => 'Parent menu router',
     'route_name' => 'menu_test.hierarchy_parent',
   );
-  $items['menu_test.hierarchy_parent.child'] = array(
+  $links['menu_test.hierarchy_parent.child'] = array(
     'link_title' => 'Child menu router',
     'route_name' => 'menu_test.hierarchy_parent_child',
     'parent' => 'menu_test.hierarchy_parent',
   );
-  $items['menu_test.hierarchy_parent.child2.child'] = array(
+  $links['menu_test.hierarchy_parent.child2.child'] = array(
     'link_title' => 'Unattached subchild router',
     'route_name' => 'menu_test.hierarchy_parent_child2',
     'parent' => 'menu_test.hierarchy_parent.child',
@@ -56,7 +56,7 @@ function menu_test_menu_link_defaults() {
   $exotic = " -._~!$'\"()*@[]?&+%#,;=:" . // "Special" ASCII characters.
     "%23%25%26%2B%2F%3F" . // Characters that look like a percent-escaped string.
     "éøïвβ中國書۞"; // Characters from various non-ASCII alphabets.
-  $items['menu_test.exotic_path'] = array(
+  $links['menu_test.exotic_path'] = array(
     'link_title' => '"Exotic" path',
     'route_name' => 'menu_test.exotic_path',
     'route_parameters' => array('exotic' => $exotic),
@@ -65,25 +65,25 @@ function menu_test_menu_link_defaults() {
   // Hidden tests; base parents.
   // Same structure as in Menu and Block modules. Since those structures can
   // change, we need to simulate our own in here.
-  $items['menu_test'] = array(
+  $links['menu_test'] = array(
     'link_title' => 'Menu test root',
     'route_name' => 'menu_test.menu_test',
   );
-  $items['menu_test.hidden'] = array(
+  $links['menu_test.hidden'] = array(
     'link_title' => 'Hidden test root',
     'route_name' => 'menu_test.hidden',
     'parent' => 'menu_test',
   );
 
   // Hidden tests; one dynamic argument.
-  $items['menu_test.hidden.menu'] = array(
+  $links['menu_test.hidden.menu'] = array(
     'link_title' => 'Menus',
     'route_name' => 'menu_test.hidden_menu',
     'parent' => 'menu_test.hidden',
   );
 
   // Hidden tests; two dynamic arguments.
-  $items['menu_test.hidden.block'] = array(
+  $links['menu_test.hidden.block'] = array(
     'link_title' => 'Blocks',
     'route_name' => 'menu_test.hidden_block',
     'parent' => 'menu_test.hidden',
@@ -91,47 +91,47 @@ function menu_test_menu_link_defaults() {
 
   // Menu trail tests.
   // @see MenuTrailTestCase
-  $items['menu_test.menu-trail'] = array(
+  $links['menu_test.menu-trail'] = array(
     'link_title' => 'Menu trail - Case 1',
     'route_name' => 'menu_test.menu_trail',
     'parent' => 'menu_test',
   );
-  $items['menu_test.admin.config.development.menu-trail'] = array(
+  $links['menu_test.admin.config.development.menu-trail'] = array(
     'link_title' => 'Menu trail - Case 2',
     'description' => 'Tests menu_tree_set_path()',
     'route_name' => 'menu_test.menu_trail_admin',
     'parent' => 'system.admin.config.development',
   );
-  $items['menu_test.custom-403-page'] = array(
+  $links['menu_test.custom-403-page'] = array(
     'link_title' => 'Custom 403 page',
     'route_name' => 'menu_test.custom_403',
     'parent' => 'menu_test',
   );
-  $items['menu_test.custom-404-page'] = array(
+  $links['menu_test.custom-404-page'] = array(
     'link_title' => 'Custom 404 page',
     'route_name' => 'menu_test.custom_404',
     'parent' => 'menu_test',
   );
   // Test the access key.
-  $items['menu_test.menu-title-test.case1'] = array(
+  $links['menu_test.menu-title-test.case1'] = array(
     'link_title' => 'Example title - Case 1',
     'route_name' => 'menu_test.title_test_case1',
   );
-  $items['menu_test.menu-title-test.case2'] = array(
+  $links['menu_test.menu-title-test.case2'] = array(
     'link_title' => 'Example title',
     'route_name' => 'menu_test.title_test_case2',
   );
-  $items['menu_test.menu-title-test.case3'] = array(
+  $links['menu_test.menu-title-test.case3'] = array(
     // Title gets completely ignored. Good thing, too.
     'link_title' => 'Bike sheds full of blue smurfs',
     'route_name' => 'menu_test.title_test_case3',
   );
-  $items['menu_test.context'] = array(
+  $links['menu_test.context'] = array(
     'link_title' => \Drupal::config('menu_test.menu_item')->get('title'),
     'route_name' => 'menu_test.context',
   );
 
-  return $items;
+  return $links;
 }
 
 /**
only in patch2:
unchanged:
--- a/core/modules/taxonomy/taxonomy.module
+++ b/core/modules/taxonomy/taxonomy.module
@@ -237,9 +237,9 @@ function taxonomy_theme() {
  * Implements hook_menu_link_defaults().
  */
 function taxonomy_menu_link_defaults() {
-  $links['taxonomy.admin.structure.vocabulary'] = array(
+  $links['taxonomy.vocabulary_list'] = array(
     'link_title' => 'Taxonomy',
-    'parent' => 'system.admin.structure',
+    'parent' => 'system.admin_structure',
     'description' => 'Manage tagging, categorization, and classification of your content.',
     'route_name' => 'taxonomy.vocabulary_list',
   );
only in patch2:
unchanged:
--- a/core/modules/tracker/tracker.module
+++ b/core/modules/tracker/tracker.module
@@ -35,7 +35,7 @@ function tracker_help($path, $arg) {
  * Implements hook_menu_link_defaults().
  */
 function tracker_menu_link_defaults() {
-  $links['tracker'] = array(
+  $links['tracker.page'] = array(
     'link_title' => 'Recent content',
     'route_name' => 'tracker.page',
   );