Bug 647820: Use -mwindows instead of -mno-cygwin on mingw compilation.  The patch is contributed by Jacek Caban <jacek@codeweavers.com>.  r=wtc.
Bug 647820: Use -mwindows instead of -mno-cygwin on mingw compilation.  The
patch is contributed by Jacek Caban <jacek@codeweavers.com>.  r=wtc.

thespooler/nss,thespooler/nss,thespooler/nss,thespooler/nss,thespooler/nss,thespooler/nss,thespooler/nss