qualify_consts: extract error_min_const_fn_violation.
qualify_consts: extract error_min_const_fn_violation.

graydon/rust,graydon/rust,graydon/rust,graydon/rust,aidancully/rust,aidancully/rust,aidancully/rust,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust,aidancully/rust