14 files declare their use of StorageComparer

ConfigImportAllTest.php in core/modules/config/tests/src/Functional/ConfigImportAllTest.php
ConfigImporterMissingContentTest.php in core/tests/Drupal/KernelTests/Core/Config/ConfigImporterMissingContentTest.php
ConfigImportRecreateTest.php in core/tests/Drupal/KernelTests/Core/Config/ConfigImportRecreateTest.php
ConfigImportRenameValidationTest.php in core/tests/Drupal/KernelTests/Core/Config/ConfigImportRenameValidationTest.php
ConfigSingleImportForm.php in core/modules/config/src/Form/ConfigSingleImportForm.php
ConfigSnapshotTest.php in core/tests/Drupal/KernelTests/Core/Config/ConfigSnapshotTest.php
ConfigSync.php in core/modules/config/src/Form/ConfigSync.php
ConfigTestTrait.php in core/tests/Drupal/Tests/ConfigTestTrait.php
ConfigUninstallViaCliImportTest.php in core/modules/config/tests/src/Kernel/ConfigUninstallViaCliImportTest.php
ContentEntityNullStorageTest.php in core/tests/Drupal/KernelTests/Core/Entity/ContentEntityNullStorageTest.php
ContentTranslationConfigImportTest.php in core/modules/content_translation/tests/src/Kernel/ContentTranslationConfigImportTest.php
install.core.inc in core/includes/install.core.inc
API functions for installing Drupal.
OverriddenConfigImportTest.php in core/modules/language/tests/src/Kernel/OverriddenConfigImportTest.php
StorageComparerTest.php in core/tests/Drupal/Tests/Core/Config/StorageComparerTest.php

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