[boost] [concept] Changeset 84470 in trunk wasn't merged to release

Hi, https://svn.boost.org/trac/boost/changeset/84470 was committed to trunk 6 months ago, but it wasn't merged to release and isn't present in 1.55.0. It fixes a blizzard of "unused local typedef" warnings with GCC 4.8. Can someone merge this to the release branch? Thanks, STL