13 files declare their use of KeyValueStoreInterface

AnnounceFetcher.php in core/modules/announcements_feed/src/AnnounceFetcher.php
CheckpointStorage.php in core/lib/Drupal/Core/Config/Checkpoint/CheckpointStorage.php
EntityAutocompleteController.php in core/modules/system/src/Controller/EntityAutocompleteController.php
EntityFieldManagerTest.php in core/tests/Drupal/Tests/Core/Entity/EntityFieldManagerTest.php
FieldDefinitionListenerTest.php in core/tests/Drupal/Tests/Core/Field/FieldDefinitionListenerTest.php
KeyValueEntityStorage.php in core/lib/Drupal/Core/Entity/KeyValueStore/KeyValueEntityStorage.php
LockFileValidator.php in core/modules/package_manager/src/Validator/LockFileValidator.php
MigrateSourceTest.php in core/modules/migrate/tests/src/Unit/MigrateSourceTest.php
StateTest.php in core/tests/Drupal/Tests/Core/State/StateTest.php
UpdateHookRegistry.php in core/lib/Drupal/Core/Update/UpdateHookRegistry.php
UpdateHookRegistryTest.php in core/tests/Drupal/Tests/Core/Update/UpdateHookRegistryTest.php
UpdateRegistry.php in core/lib/Drupal/Core/Update/UpdateRegistry.php
UpdateRegistryTest.php in core/tests/Drupal/Tests/Core/Update/UpdateRegistryTest.php

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