Applied this change and afterwards, selecting "Working Copy" on `/drydock/blueprint/edit/form/default/` does not show a RuntimeException on strlen() anymore. Instead, it shows a PhutilAggregateException covered in T15408.
Try also creating an integer "Custom Field" in some applications like Maniphest (maniphest.custom-field-definitions)
or in the People component (user.custom-field-definitions) etc., populating the related forms with your usual fuzzy tests.