[MSan] Implement __sanitizer_print_stack_trace().

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@209625 91177308-0d34-0410-b5e6-96231b3b80d8
[ASan tests] Use ASAN_OPTIONS in a portable way

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@209629 91177308-0d34-0410-b5e6-96231b3b80d8