tsan: add a test that used to crash, fixed by r180180.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@180251 91177308-0d34-0410-b5e6-96231b3b80d8
[ASan] Add allow_user_segv_handler to let users override SEGV handler installed by ASan

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@180255 91177308-0d34-0410-b5e6-96231b3b80d8