9 files declare their use of KeyValueStoreInterface

EntityAutocompleteController.php in core/modules/system/src/Controller/EntityAutocompleteController.php
EntityFieldManagerTest.php in core/tests/Drupal/Tests/Core/Entity/EntityFieldManagerTest.php
Contains \Drupal\Tests\Core\Entity\EntityFieldManagerTest.
FieldDefinitionListenerTest.php in core/tests/Drupal/Tests/Core/Field/FieldDefinitionListenerTest.php
KeyValueEntityStorage.php in core/lib/Drupal/Core/Entity/KeyValueStore/KeyValueEntityStorage.php
MigrateSourceTest.php in core/modules/migrate/tests/src/Unit/MigrateSourceTest.php
Contains \Drupal\Tests\migrate\Unit\MigrateSourceTest.
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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