Many of the test executables use pthreads directly. This isn't
portable on Windows, so this patch converts these test to use
C++11 threads and mutexes. Since Windows' implementation of
std::thread classes throw and catch from header files, this patch
also disables exceptions when compiling with clang on Windows.
Reviewed by: Todd Fiala, Ed Maste
Differential Revision: http://reviews.llvm.org/D4816
llvm-svn: 215562