All classes that implement TranslationInterface in Drupal 8

class \Drupal\Core\StringTranslation\TranslationManager implements TranslationInterface, TranslatorInterface
class \Drupal\Tests\Core\StringTranslation\TestTranslationManager
class \Drupal\Tests\automatic_updates\Kernel\ReadinessValidation\TestTranslationManager implements TranslationInterface
class \Drupal\Tests\automatic_updates\Unit\TestTranslationManager implements TranslationInterface
class \Drupal\Tests\plugin\Unit\TranslationMock implements TranslationInterface
class \Drupal\Tests\user\Unit\TestTranslationManager implements TranslationInterface
class \Drupal\webprofiler\StringTranslation\TranslationManagerWrapper
class \Drupal\webprofiler\StringTranslation\TranslationManagerWrapper
class \Drupal\webprofiler\StringTranslation\TranslationManagerWrapper

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