Deprecate add_object_page() and add_utility_page()

[SergeyBiryukov]

add_object_page() and add_utility_page() are not used in core and are just wrappers which pass $_wp_last_object_menu++ and $_wp_last_utility_menu++, respectively, to add_menu_page().

This can lead to a conflict with other menu items added by plugins, see #23095.

[SergeyBiryukov]

Related: [9537], [9949], [11856].

[ocean90]

+1

[chriscct7]

+1

[ocean90]

23108.2.patch​ adds the _deprecated_function() calls.

[jamesgol]

Just ran into an issue with a plugin using add_object_page on too many items and overwriting other entries. Searched for an issue and ended up here.

I'd agree this should be deprecated but for the time being why not just ditch the whole $_wp_last_object_menu++; in add_object_page and have it pass null to add_menu_page?

[swissspidy]

In 35874:

Admin Menu: Deprecate add_object_page() and add_utility_page().

These functions are not used in core and are just wrappers for add_menu_page().

Fixes #23108.