Thread: Added #8508 test.

git-svn-id: http://svn.boost.org/svn/boost/trunk@84097 b8fc166d-592f-0410-95f2-cb63ce0dd405
Thread: replace boost:tuple in async_func.hpp as not movable until the patch is applied.

git-svn-id: http://svn.boost.org/svn/boost/trunk@84098 b8fc166d-592f-0410-95f2-cb63ce0dd405