Add asan/msan to the list of available features in LIT test runner. Mark ASan-unfriendly test as XFAIL.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177995 91177308-0d34-0410-b5e6-96231b3b80d8
Actually mark ASan-unfriendly test as XFAIL

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177997 91177308-0d34-0410-b5e6-96231b3b80d8