These tests started passing after libcxxabi's r255559, which fixed a problem
relating to how libcxxabi links its EH library. The test failures were
caused by an issue with libc++, not the sanitizers (confirmed by building a
pre-r255559 revision with libc++/libc++abi and without sanitizers), so they
should never have been XFAILed under the sanitizers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255708 91177308-0d34-0410-b5e6-96231b3b80d8
