18 files declare their use of BatchBuilder

BatchBuilderTest.php in core/tests/Drupal/Tests/Core/Batch/BatchBuilderTest.php
BatchTestController.php in core/modules/system/tests/modules/batch_test/src/Controller/BatchTestController.php
batch_test.module in core/modules/system/tests/modules/batch_test/batch_test.module
ConfigSingleImportForm.php in core/modules/config/src/Form/ConfigSingleImportForm.php
ConfigSync.php in core/modules/config/src/Form/ConfigSync.php
DbUpdateController.php in core/modules/system/src/Controller/DbUpdateController.php
install.core.inc in core/includes/install.core.inc
API functions for installing Drupal.
locale.bulk.inc in core/modules/locale/locale.bulk.inc
locale.compare.inc in core/modules/locale/locale.compare.inc
locale.fetch.inc in core/modules/locale/locale.fetch.inc
node.admin.inc in core/modules/node/node.admin.inc
node.module in core/modules/node/node.module
PrepareModulesEntityUninstallForm.php in core/modules/system/src/Form/PrepareModulesEntityUninstallForm.php
ReviewForm.php in core/modules/migrate_drupal_ui/src/Form/ReviewForm.php
update.authorize.inc in core/modules/update/update.authorize.inc
UpdateController.php in core/modules/update/src/Controller/UpdateController.php
UpdateManagerUpdate.php in core/modules/update/src/Form/UpdateManagerUpdate.php
user.module in core/modules/user/user.module

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