dev-libs/cyrus-sasl does not have an SELinux use flag and it does not pull in sec-policy/selinux-sasl. Also net-misc/bridge-utils does not pull in sec-policy/selinux-brctl
there is a separate bug for bridge-utils already, bug 538022. Next time there is a bump / release of cyrus-sasl, please add IUSE="selinux" RDEPEND="selinux? ( sec-policy/selinux-sasl )" see the blocker bug for more info.
+ 06 Jun 2015; Jason Zaman <perfinion@gentoo.org> cyrus-sasl-2.1.26-r9.ebuild: + RDEP on selinux policy, bug 543568 added the dep.