hook_node_submit() is depcrecated and should be removed

Motivation

hook_node_validate() and hook_node_submit() are hooks which can be considered already deprecated in d7: No other entity types have them and it's not best practice to use them: Instead, you should use a form element validation and a form builder callback to extract form values.

Proposed resolution

Convert menu_ui_node_submit() an entity builder and remove it.

Remaining tasks

-

User interface changes

API changes

hook_node_submit() would be removed