33 files declare their use of TranslationInterface

AlreadyInstalledException.php in core/lib/Drupal/Core/Installer/Exception/AlreadyInstalledException.php
BreakpointManager.php in core/modules/breakpoint/src/BreakpointManager.php
CommentLinkBuilder.php in core/modules/comment/src/CommentLinkBuilder.php
CommentManager.php in core/modules/comment/src/CommentManager.php
ConfigImporter.php in core/lib/Drupal/Core/Config/ConfigImporter.php
ConfigManager.php in core/lib/Drupal/Core/Config/ConfigManager.php
ContentUninstallValidator.php in core/lib/Drupal/Core/Entity/ContentUninstallValidator.php
DatabaseDriverUninstallValidator.php in core/lib/Drupal/Core/Extension/DatabaseDriverUninstallValidator.php
DateFormatter.php in core/lib/Drupal/Core/Datetime/DateFormatter.php
EntityActionDeriverBase.php in core/lib/Drupal/Core/Action/Plugin/Action/Derivative/EntityActionDeriverBase.php
EntityController.php in core/lib/Drupal/Core/Entity/Controller/EntityController.php
EntityFieldManagerTest.php in core/tests/Drupal/Tests/Core/Entity/EntityFieldManagerTest.php
Contains \Drupal\Tests\Core\Entity\EntityFieldManagerTest.
EntityFormInterface.php in core/lib/Drupal/Core/Entity/EntityFormInterface.php
EntityTypeManager.php in core/lib/Drupal/Core/Entity/EntityTypeManager.php
EntityTypeManagerTest.php in core/tests/Drupal/Tests/Core/Entity/EntityTypeManagerTest.php
Contains \Drupal\Tests\Core\Entity\EntityTypeManagerTest.
FormAjaxSubscriber.php in core/lib/Drupal/Core/Form/EventSubscriber/FormAjaxSubscriber.php
FormValidator.php in core/lib/Drupal/Core/Form/FormValidator.php
MailManager.php in core/lib/Drupal/Core/Mail/MailManager.php
MaintenanceModeSubscriber.php in core/lib/Drupal/Core/EventSubscriber/MaintenanceModeSubscriber.php
MenuLinkDefaultForm.php in core/lib/Drupal/Core/Menu/Form/MenuLinkDefaultForm.php
MenuParentFormSelector.php in core/lib/Drupal/Core/Menu/MenuParentFormSelector.php
ModuleRequiredByThemesUninstallValidator.php in core/lib/Drupal/Core/Extension/ModuleRequiredByThemesUninstallValidator.php
NoProfilesException.php in core/lib/Drupal/Core/Installer/Exception/NoProfilesException.php
PermissionHandler.php in core/modules/user/src/PermissionHandler.php
PermissionHandlerTest.php in core/modules/user/tests/src/Unit/PermissionHandlerTest.php
Contains \Drupal\Tests\user\Unit\PermissionHandlerTest.
RequiredModuleUninstallValidator.php in core/lib/Drupal/Core/Extension/RequiredModuleUninstallValidator.php
SettingsForm.php in core/modules/aggregator/src/Form/SettingsForm.php
StringTranslationTraitTest.php in core/tests/Drupal/Tests/Core/StringTranslation/StringTranslationTraitTest.php
TitleResolver.php in core/lib/Drupal/Core/Controller/TitleResolver.php
TranslatableMarkupTest.php in core/tests/Drupal/Tests/Core/StringTranslation/TranslatableMarkupTest.php
UnmetDependenciesException.php in core/lib/Drupal/Core/Config/UnmetDependenciesException.php
UpdateManager.php in core/modules/update/src/UpdateManager.php
UserLocalTask.php in core/modules/user/src/Plugin/Derivative/UserLocalTask.php

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