11 files declare their use of UserStorageInterface in Drupal 8

CommentNameConstraintValidator.php in core/modules/comment/src/Plugin/Validation/Constraint/CommentNameConstraintValidator.php

ProtectedUserFieldConstraintValidator.php in core/modules/user/src/Plugin/Validation/Constraint/ProtectedUserFieldConstraintValidator.php

SiteConfigureForm.php in core/lib/Drupal/Core/Installer/Form/SiteConfigureForm.php

UserAuthenticationController.php in core/modules/user/src/Controller/UserAuthenticationController.php

UserController.php in core/modules/user/src/Controller/UserController.php

UserControllerTest.php in core/modules/user/tests/src/Kernel/Controller/UserControllerTest.php

UserLoginForm.php in core/modules/user/src/Form/UserLoginForm.php

UserMailRequiredValidatorTest.php in core/modules/user/tests/src/Unit/Plugin/Validation/Constraint/UserMailRequiredValidatorTest.php

UserMultipleCancelConfirm.php in core/modules/user/src/Form/UserMultipleCancelConfirm.php

UserPasswordForm.php in core/modules/user/src/Form/UserPasswordForm.php

UserPasswordFormTest.php in core/modules/user/tests/src/Kernel/Form/UserPasswordFormTest.php