Merge branch 'master' of http://llvm.org/git/libcxxabi
Add support for LLVM_USE_SANITIZER=Thread to test suite

git-svn-id: https://llvm.org/svn/llvm-project/libcxxabi/trunk@222260 91177308-0d34-0410-b5e6-96231b3b80d8
Merge branch 'master' of http://llvm.org/git/libcxxabi
Merge branch 'master' of github.com:efcs/libcxxabi