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/numerics/rand/rand.predef/knuth_b.pass.cpp

@@ -0,0 +1,22 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <random>
+
+// typedef shuffle_order_engine<minstd_rand0, 256>                      knuth_b;
+
+#include <random>
+#include <cassert>
+
+int main()
+{
+    std::knuth_b e;
+    e.discard(9999);
+    assert(e() == 1112339016u);
+}