coroutine: fix standard_allocator issue for Windows


git-svn-id: http://svn.boost.org/svn/boost/trunk@86567 b8fc166d-592f-0410-95f2-cb63ce0dd405
Thread: avoid thread ambiguity on vacpp tester.

git-svn-id: http://svn.boost.org/svn/boost/trunk@86568 b8fc166d-592f-0410-95f2-cb63ce0dd405
Thread: added test for #9303.

git-svn-id: http://svn.boost.org/svn/boost/trunk@86569 b8fc166d-592f-0410-95f2-cb63ce0dd405