LGTM, thanks!
https://codereview.appspot.com/571190043/diff/559290043/lily/system.cc File lily/system.cc (right): https://codereview.appspot.com/571190043/diff/559290043/lily/system.cc#newcode525 lily/system.cc:525: { Is there a reason for grouping the code into additional braces? https://codereview.appspot.com/571190043/
