ArchiverManager.php in core/lib/Drupal/Core/Archiver/ArchiverManager.php
ContainerFactory.php in core/lib/Drupal/Core/Plugin/Factory/ContainerFactory.php
DefaultFactoryTest.php in core/tests/Drupal/Tests/Component/Plugin/DefaultFactoryTest.php
DefaultsTestPluginManager.php in core/modules/system/tests/modules/plugin_test/src/Plugin/DefaultsTestPluginManager.php
FormatterPluginManager.php in core/lib/Drupal/Core/Field/FormatterPluginManager.php
MigratePluginManager.php in core/modules/migrate/src/Plugin/MigratePluginManager.php
PluginExistsConstraintValidator.php in core/lib/Drupal/Core/Plugin/Plugin/Validation/Constraint/PluginExistsConstraintValidator.php
TestPluginManager.php in core/modules/system/tests/modules/plugin_test/src/Plugin/TestPluginManager.php
TestPluginManager.php in core/tests/Drupal/Tests/Core/Plugin/TestPluginManager.php
WidgetPluginManager.php in core/lib/Drupal/Core/Field/WidgetPluginManager.php