Use something really explicit to test "move semantics" on builds without
r-value references. I still want to test that when we have them,
llvm_move is actually a move.

Have I mentioned that I really want to move to C++11? ;]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194318 91177308-0d34-0410-b5e6-96231b3b80d8