29 files declare their use of DrupalKernel

common.inc in core/includes/common.inc
Common functions that many Drupal modules will need to reference.
DiscoverServiceProvidersTest.php in core/tests/Drupal/Tests/Core/DrupalKernel/DiscoverServiceProvidersTest.php
DistributionProfileExistingSettingsTest.php in core/tests/Drupal/FunctionalTests/Installer/DistributionProfileExistingSettingsTest.php
DrupalKernelLegacyTest.php in core/tests/Drupal/Tests/Core/DrupalKernel/DrupalKernelLegacyTest.php
DrupalKernelTest.php in core/tests/Drupal/Tests/Core/DrupalKernel/DrupalKernelTest.php
DrupalKernelTest.php in core/tests/Drupal/KernelTests/Core/DrupalKernel/DrupalKernelTest.php
ExtensionDiscovery.php in core/lib/Drupal/Core/Extension/ExtensionDiscovery.php
FunctionalTestSetupTrait.php in core/lib/Drupal/Core/Test/FunctionalTestSetupTrait.php
index.php in core/assets/scaffold/files/index.php
The PHP page that serves all page requests on a Drupal installation.
install.core.inc in core/includes/install.core.inc
API functions for installing Drupal.
InstallCommand.php in core/lib/Drupal/Core/Command/InstallCommand.php
InstallerExistingSettingsNoProfileTest.php in core/tests/Drupal/FunctionalTests/Installer/InstallerExistingSettingsNoProfileTest.php
InstallerExistingSettingsTest.php in core/tests/Drupal/FunctionalTests/Installer/InstallerExistingSettingsTest.php
InstallerKernel.php in core/lib/Drupal/Core/Installer/InstallerKernel.php
InstallerTestBase.php in core/tests/Drupal/FunctionalTests/Installer/InstallerTestBase.php
KernelTestBase.php in core/tests/Drupal/KernelTests/KernelTestBase.php
PublicStream.php in core/lib/Drupal/Core/StreamWrapper/PublicStream.php
rebuild.php in core/rebuild.php
Rebuilds all Drupal caches even when Drupal itself does not work.
ReplicaKillSwitchTest.php in core/tests/Drupal/KernelTests/Core/Database/ReplicaKillSwitchTest.php
ServerCommand.php in core/lib/Drupal/Core/Command/ServerCommand.php
StreamWrapperTest.php in core/tests/Drupal/KernelTests/Core/File/StreamWrapperTest.php
system.install in core/modules/system/system.install
Install, update and uninstall functions for the system module.
TestDiscoveryTest.php in core/tests/Drupal/Tests/Core/Test/TestDiscoveryTest.php
TestKernel.php in core/lib/Drupal/Core/Test/TestKernel.php
TestRunnerKernel.php in core/lib/Drupal/Core/Test/TestRunnerKernel.php
TestSiteUserLoginCommand.php in core/tests/Drupal/TestSite/Commands/TestSiteUserLoginCommand.php
UpdateKernel.php in core/lib/Drupal/Core/Update/UpdateKernel.php
utility.inc in core/includes/utility.inc
Miscellaneous functions.
ValidateHostnameTest.php in core/tests/Drupal/Tests/Core/DrupalKernel/ValidateHostnameTest.php

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