dgram: call send callback asynchronously
According to this issue https://github.com/iojs/io.js/pull/486, every callbacks should be called asynchronously, But dgram.send
callback is not called asynchronously.
We can not run full benchmark test. benchmark/net/dgram.js
uses send callback recursively.
But send callback is not asynchronous, the recursive callback goes infinite loop.
If this fix is accepted, we could run full benchmark test on every release.
I think libuv changes the uv_udp_send API on this commit https://github.com/libuv/libuv/commit/41891222bca4e985bef45515fe131fbdbec3f969.
So I just fixed callback asynchronously using setImmediate
.