Admin menu quick links (patch included)

Since two form submission handlers are added to the system_performance_settings form, what is the benefit of implementing this hook too?

hook_admin_menu_cache_info() is thought for modules that use a specific cache bin to store their data. This module implements a cache backend; it does not use a cache bin for its own data.
The APCu extension is no longer used to cache PHP opcode. If implementing hook_admin_menu_cache_info() made sense with the APC extension, no longer supported, it does not make sense with the APCu extension.