please, add a new db-level privilege SHOW CREATE ROUTINE so that the user with ALL PRIVILEGES on db level would be able to see all routines in that db
Update after discussing with Serg:
EXECUTE_ACL CREATE_PROC_ACL ALTER_PROC_ACL allow to get info about the routine, but SHOW_CREATE_ROUTINE_ACL should give the text.
This privilege related to PROCEDURE or FUNCTION or PACKAGE.
The effect of this MDEV is that one can give a user the 'show create routine' privilege, which allows the user to see the procedure text: