35 files declare their use of RouteProviderInterface

AccessManager.php in core/lib/Drupal/Core/Access/AccessManager.php
BlockContentAddLocalAction.php in core/modules/block_content/src/Plugin/Menu/LocalAction/BlockContentAddLocalAction.php
ConfigEntityMapper.php in core/modules/config_translation/src/ConfigEntityMapper.php
ConfigNamesMapper.php in core/modules/config_translation/src/ConfigNamesMapper.php
Feed.php in core/modules/views/src/Plugin/views/display/Feed.php
FieldUiLocalAction.php in core/modules/field_ui/src/Plugin/Derivative/FieldUiLocalAction.php
FieldUiLocalTask.php in core/modules/field_ui/src/Plugin/Derivative/FieldUiLocalTask.php
Language.php in core/modules/ckeditor5/src/Plugin/CKEditor5Plugin/Language.php
LanguagePluginTest.php in core/modules/ckeditor5/tests/src/Unit/LanguagePluginTest.php
LazyRouteCollectionTest.php in core/tests/Drupal/Tests/Core/Routing/LazyRouteCollectionTest.php
LocalActionDefault.php in core/lib/Drupal/Core/Menu/LocalActionDefault.php
LocalActionManager.php in core/lib/Drupal/Core/Menu/LocalActionManager.php
LocalActionManagerTest.php in core/tests/Drupal/Tests/Core/Menu/LocalActionManagerTest.php
LocalTaskDefaultTest.php in core/tests/Drupal/Tests/Core/Menu/LocalTaskDefaultTest.php
LocalTaskManager.php in core/lib/Drupal/Core/Menu/LocalTaskManager.php
MenuLinkAdd.php in core/modules/menu_ui/src/Plugin/Menu/LocalAction/MenuLinkAdd.php
MenuLinkTree.php in core/lib/Drupal/Core/Menu/MenuLinkTree.php
MockRouteProvider.php in core/modules/system/src/Tests/Routing/MockRouteProvider.php
NavigationContentLinks.php in core/modules/navigation/src/NavigationContentLinks.php
OptionsRequestSubscriber.php in core/lib/Drupal/Core/EventSubscriber/OptionsRequestSubscriber.php
OptionsRequestSubscriberTest.php in core/tests/Drupal/Tests/Core/EventSubscriber/OptionsRequestSubscriberTest.php
Page.php in core/modules/views/src/Plugin/views/display/Page.php
PathPluginBase.php in core/modules/views/src/Plugin/views/display/PathPluginBase.php
RestExport.php in core/modules/rest/src/Plugin/views/display/RestExport.php
ResultTest.php in core/modules/views/tests/src/Unit/Plugin/area/ResultTest.php
RouterTest.php in core/tests/Drupal/Tests/Core/Routing/RouterTest.php
RouterUnsupportedTest.php in core/tests/Drupal/Tests/Core/Routing/RouterUnsupportedTest.php
TestLocalActionWithConfig.php in core/modules/system/tests/modules/menu_test/src/Plugin/Menu/LocalAction/TestLocalActionWithConfig.php
UrlGeneratorTest.php in core/tests/Drupal/Tests/Core/Routing/UrlGeneratorTest.php
UserAuthenticationController.php in core/modules/user/src/Controller/UserAuthenticationController.php
ViewExecutable.php in core/modules/views/src/ViewExecutable.php
ViewExecutableFactory.php in core/modules/views/src/ViewExecutableFactory.php
ViewsLocalTask.php in core/modules/views/src/Plugin/Derivative/ViewsLocalTask.php
WorkspaceRequestSubscriber.php in core/modules/workspaces/src/EventSubscriber/WorkspaceRequestSubscriber.php
WorkspaceRequestSubscriberTest.php in core/modules/workspaces/tests/src/Unit/WorkspaceRequestSubscriberTest.php

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