Summary:
This patch adds a "REQUIRES-ANY" feature test that is disjunctive. This marks a test as `UNSUPPORTED` if none of the specified features are available.
Libc++ has the need to write feature test such as `// REQUIRES-ANY: c++98, c++03` when testing of behavior that is specific to older dialects but has since changed.
Reviewers: rnk, ddunbar
Subscribers: ddunbar, probinson, llvm-commits, cfe-commits
Differential Revision: http://reviews.llvm.org/D20757
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271468 91177308-0d34-0410-b5e6-96231b3b80d8
960b5867c5