einfo messages are not logged and are not displayed in the summary at the end of emerge output, so you don't see them unless busybox is the last package installed by an emerge invocation. Actually in this case the message is mostly redundant with the savedconfig.eclass output, so maybe it should just be removed. Reproducible: Always
http://sources.gentoo.org/sys-apps/busybox/busybox-1.18.5.ebuild?r1=1.1&r2=1.2