added a function and a trait util from stl
added a function and a trait util from stl

(cherry picked from commit 2ea8127e629ee26a48bbaeda8da935dbe04d7ebe)

root-mirror/cling,marsupial/cling,perovic/cling,karies/cling,perovic/cling,karies/cling,root-mirror/cling,karies/cling,root-mirror/cling,karies/cling,perovic/cling,root-mirror/cling,marsupial/cling,marsupial/cling,karies/cling,perovic/cling,marsupial/cling,karies/cling,perovic/cling,marsupial/cling,root-mirror/cling,marsupial/cling,root-mirror/cling