12 files declare their use of DrupalKernelInterface

AutowireTest.php in core/tests/Drupal/KernelTests/Core/DependencyInjection/AutowireTest.php
BootableCommandTrait.php in core/lib/Drupal/Core/Command/BootableCommandTrait.php
DevelopmentSettingsForm.php in core/modules/system/src/Form/DevelopmentSettingsForm.php
DrupalKernelTest.php in core/tests/Drupal/KernelTests/Core/DrupalKernel/DrupalKernelTest.php
KernelPreHandle.php in core/lib/Drupal/Core/StackMiddleware/KernelPreHandle.php
LanguageRequestSubscriber.php in core/modules/language/src/EventSubscriber/LanguageRequestSubscriber.php
ModifyServiceDefinitionsPass.php in core/lib/Drupal/Core/DependencyInjection/Compiler/ModifyServiceDefinitionsPass.php
ModuleInstaller.php in core/lib/Drupal/Core/Extension/ModuleInstaller.php
ServerCommand.php in core/lib/Drupal/Core/Command/ServerCommand.php
TestController.php in core/modules/system/tests/modules/container_rebuild_test/src/TestController.php
TestService.php in core/modules/system/tests/modules/autowire_test/src/TestService.php
UpdateRoot.php in core/modules/update/src/UpdateRoot.php

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