Implement the default searcher for std::experimental::search.

llvm-svn: 242682
diff --git a/libcxx/test/std/experimental/func/header.functional.synop/includes.pass.cpp b/libcxx/test/std/experimental/func/header.functional.synop/includes.pass.cpp
new file mode 100644
index 0000000..1b72d4a
--- /dev/null
+++ b/libcxx/test/std/experimental/func/header.functional.synop/includes.pass.cpp
@@ -0,0 +1,21 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11
+
+// <experimental/functional>
+//
+//  has to include <functional>
+
+#include <experimental/functional>
+
+int main()
+{
+  std::function<int(int)> x;
+}