node: revert removal of MakeCallback
node: revert removal of MakeCallback

In 0168109 an implementation of MakeCallback was accidently removed. It
has been re-added.

dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node