Move test into test/std subdirectory.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@224658 91177308-0d34-0410-b5e6-96231b3b80d8

test/std/experimental/optional/optional.syn/optional_const_nullopt_t.fail.cpp

@@ -0,0 +1,28 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <optional>
+
+// A program that necessitates the instantiation of template optional for
+// (possibly cv-qualified) null_opt_t is ill-formed.
+
+#include <experimental/optional>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11
+    using std::experimental::optional;
+    using std::experimental::nullopt_t;
+    using std::experimental::nullopt;
+
+    optional<const nullopt_t> opt;
+#else
+#error
+#endif  // _LIBCPP_STD_VER > 11
+}