17 files declare their use of AccessResultInterface

AccessResultTest.php in core/tests/Drupal/Tests/Core/Access/AccessResultTest.php
AnnounceBlock.php in core/modules/announcements_feed/src/Plugin/Block/AnnounceBlock.php
BlockContentAccessControlHandler.php in core/modules/block_content/src/BlockContentAccessControlHandler.php
Element.php in core/lib/Drupal/Core/Render/Element.php
EntityPermissionsForm.php in core/modules/user/src/Form/EntityPermissionsForm.php
FieldReuseAccessCheck.php in core/modules/field_ui/src/Access/FieldReuseAccessCheck.php
FormBuilder.php in core/lib/Drupal/Core/Form/FormBuilder.php
LinksetController.php in core/modules/system/src/Controller/LinksetController.php
MenuLinkTree.php in core/lib/Drupal/Core/Menu/MenuLinkTree.php
NavigationSectionStorage.php in core/modules/navigation/src/Plugin/SectionStorage/NavigationSectionStorage.php
NavigationShortcutsBlock.php in core/modules/navigation/src/Plugin/Block/NavigationShortcutsBlock.php
PrepareModulesEntityUninstallForm.php in core/modules/system/src/Form/PrepareModulesEntityUninstallForm.php
Renderer.php in core/lib/Drupal/Core/Render/Renderer.php
RendererTest.php in core/tests/Drupal/Tests/Core/Render/RendererTest.php
SystemAdminMenuBlockAccessCheck.php in core/modules/system/src/Access/SystemAdminMenuBlockAccessCheck.php
TestAction.php in core/modules/views/tests/modules/action_bulk_test/src/Plugin/Action/TestAction.php
UserPermissionsModuleSpecificForm.php in core/modules/user/src/Form/UserPermissionsModuleSpecificForm.php

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