18 files declare their use of InstallStorage

ConfigAfterInstallerTestBase.php in core/tests/Drupal/FunctionalTests/Installer/ConfigAfterInstallerTestBase.php
ConfigImportUITest.php in core/modules/config/tests/src/Functional/ConfigImportUITest.php
ConfigInstallProfileOverrideTest.php in core/modules/config/tests/src/Functional/ConfigInstallProfileOverrideTest.php
ConfigInstallProfileUnmetDependenciesTest.php in core/modules/config/tests/src/Functional/ConfigInstallProfileUnmetDependenciesTest.php
ConfigInstallTest.php in core/tests/Drupal/KernelTests/Core/Config/ConfigInstallTest.php
ConfigSchemaTest.php in core/tests/Drupal/KernelTests/Core/Config/ConfigSchemaTest.php
DefaultConfigTest.php in core/tests/Drupal/KernelTests/Config/DefaultConfigTest.php
DemoUmamiProfileTest.php in core/profiles/demo_umami/tests/src/Functional/DemoUmamiProfileTest.php
EntityTypeWithoutViewsDataTest.php in core/modules/datetime_range/tests/src/Kernel/Views/EntityTypeWithoutViewsDataTest.php
ExtensionInstallStorageTest.php in core/tests/Drupal/Tests/Core/Config/ExtensionInstallStorageTest.php
FunctionalTestSetupTrait.php in core/lib/Drupal/Core/Test/FunctionalTestSetupTrait.php
language.module in core/modules/language/language.module
Add language handling functionality to Drupal.
MediaDisplayTest.php in core/modules/media/tests/src/FunctionalJavascript/MediaDisplayTest.php
ModuleTestBase.php in core/modules/system/tests/src/Functional/Module/ModuleTestBase.php
RecipeRunner.php in core/lib/Drupal/Core/Recipe/RecipeRunner.php
TestInstallStorage.php in core/modules/config/tests/config_test/src/TestInstallStorage.php
TestViewsTest.php in core/modules/views/tests/src/Kernel/TestViewsTest.php
ThemeSettingsTest.php in core/tests/Drupal/KernelTests/Core/Theme/ThemeSettingsTest.php

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