6 files declare their use of FactoryInterface

LocalActionManagerTest.php in core/tests/Drupal/Tests/Core/Menu/LocalActionManagerTest.php
LocalTaskIntegrationTestBase.php in core/tests/Drupal/Tests/Core/Menu/LocalTaskIntegrationTestBase.php
LocalTaskManagerTest.php in core/tests/Drupal/Tests/Core/Menu/LocalTaskManagerTest.php
PluginManagerInterface.php in core/lib/Drupal/Component/Plugin/PluginManagerInterface.php
SectionStorageManagerTest.php in core/modules/layout_builder/tests/src/Unit/SectionStorageManagerTest.php
ViewsHandlerManagerTest.php in core/modules/views/tests/src/Unit/ViewsHandlerManagerTest.php

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