9 files declare their use of State in Drupal 9

ContentModerationConfigureForm.php in core/modules/content_moderation/src/Form/ContentModerationConfigureForm.php

Permissions.php in core/modules/content_moderation/src/Permissions.php

PredefinedStatesWorkflowTestType.php in core/modules/workflows/tests/modules/workflow_type_test/src/Plugin/WorkflowType/PredefinedStatesWorkflowTestType.php

StateTest.php in core/modules/workflows/tests/src/Unit/StateTest.php

WorkflowEditForm.php in core/modules/workflows/src/Form/WorkflowEditForm.php

WorkflowTest.php in core/modules/workflows/tests/src/Unit/WorkflowTest.php

WorkflowTransitionAddForm.php in core/modules/workflows/src/Form/WorkflowTransitionAddForm.php

WorkflowTransitionEditForm.php in core/modules/workflows/src/Form/WorkflowTransitionEditForm.php

WorkflowTypeBase.php in core/modules/workflows/src/Plugin/WorkflowTypeBase.php