9 files declare their use of FileStorage in Zircon Profile 8

CachedStorageTest.php in core/modules/config/src/Tests/Storage/CachedStorageTest.php

Contains \Drupal\config\Tests\Storage\CachedStorageTest.

ConfigAfterInstallerTestBase.php in core/modules/system/src/Tests/Installer/ConfigAfterInstallerTestBase.php

Contains \Drupal\system\Tests\Installer\ConfigAfterInstallerTestBase.

ConfigFileContentTest.php in core/modules/config/src/Tests/ConfigFileContentTest.php

Contains \Drupal\config\Tests\ConfigFileContentTest.

ConfigInstallProfileOverrideTest.php in core/modules/config/src/Tests/ConfigInstallProfileOverrideTest.php

Contains \Drupal\config\Tests\ConfigInstallProfileOverrideTest.

ConfigSchemaTest.php in core/modules/config/src/Tests/ConfigSchemaTest.php

Contains \Drupal\config\Tests\ConfigSchemaTest.

DefaultConfigTest.php in core/tests/Drupal/KernelTests/Config/DefaultConfigTest.php

Contains \Drupal\KernelTests\Config\DefaultConfigTest.

FileStorageTest.php in core/modules/config/src/Tests/Storage/FileStorageTest.php

Contains \Drupal\config\Tests\Storage\FileStorageTest.

ModuleTestBase.php in core/modules/system/src/Tests/Module/ModuleTestBase.php

Contains \Drupal\system\Tests\Module\ModuleTestBase.

ViewTestData.php in core/modules/views/src/Tests/ViewTestData.php

Contains \Drupal\views\Tests\ViewTestData.