Gravity Forms 2.8.9

- Added the gform_is_valid_formula_form_editor JS filter allowing the formula validation result to be overridden in the form editor.
- Fixed multiple forms being created when hitting enter on the submit button in the Create Form modal.
- Updated usage of .screen-reader-text usage to be uniform with WordPress core.

- Fixed a PHP notice which occurs when paging and a List type field is hidden by conditional logic.
- Updated file deletion to not utilize WP_CONTENT_DIR and WP_CONTENT_URL.
- API: Fixed an issue with GFAPI:get_field() for sub fields of a Repeater field.
- Fixed issue where default and dynamically populated values in Single Product, Single Shipping and HTML5 input types were not correctly reset when hidden by conditional logic.

- Reverted conditional logic change in 2.4.6 which introduced performance issues for some form configurations.
- AF: Fixed Payment Add-On feeds not deactivating when deleting a credit card field from form.