my webRTC implements never calls onaddstream - webrtc

Question

I am using https://github.com/HenrikJoreteg/RTCPeerConnection which simplifies WebRTC but still cannot get it works. WebRTC peer connection (offer, answer, ice) get established but onaddstream never gets call.
(I open 2 browser tab with the same html which utilize the following code and I run the code by running start function to get the video and then running peer the start the connection.)
Can anyone help me point me out the bug in this code?
var local_stream;
var localvid = document.getElementById('localvid');
var remotevid = document.getElementById('remotevid');
var servers= {iceServers: [{"url": "stun:stun.l.google.com:19302"}]};
var constraints = {optional: [{"DtlsSrtpKeyAgreement": true}]};
var peerConn = new PeerConnection(servers,constraints);
function start(){
navigator.getUserMedia ||
(navigator.getUserMedia = navigator.getUserMedia || navigator.mozGetUserMedia ||
  navigator.webkitGetUserMedia || navigator.msGetUserMedia);
if (navigator.getUserMedia) {
navigator.getUserMedia({
      video: true,
      audio: false
    }, onSuccess, function(){});
} else {
    alert('getUserMedia is not supported in this browser.');
}
}
function onSuccess(stream){
localvid.src = window.webkitURL.createObjectURL(stream);
local_stream = stream;
localvid.autoplay = true;
}
function peer(){
peerConn.addStream(local_stream);
peerConn.offer({ mandatory: { OfferToReceiveAudio:false, OfferToReceiveVideo: true} },
function( err, offer){
if(!err){
console.log("Creating an offer...");
socket.emit('offer',offer);
}
}
);
}
peerConn.on('ice', function(candidate){
if(candidate){
console.log("Sending ice...");console.log(candidate);
socket.emit('ice',candidate);
}else { console.log("End of candidates.");}
});
peerConn.on('streamAdded',function(stream){
console.log("Adding stream..");
remotevid.src = window.webkitURL.createObjectURL(stream);
remotevid.autoplay = true;
});
socket.on('offer',function(offer){
peerConn.answer(offer,function (err,answer){
if(!err){
console.log("Creating the answer...");console.log(answer);
socket.emit('answer',answer);
}
});
});
socket.on('answer', function(answer){
console.log("Got the answer...");
peerConn.handleAnswer(answer);
});
socket.on('ice', function (candidate){
console.log("Processing ice...");
peerConn.processIce(candidate);
console.log(candidate);
});

Answer 1

OK. I got it to work now.
https://github.com/HenrikJoreteg/RTCPeerConnection
The document there is so wrong...
There is no 'streamAdded' event but 'addStream' event and the value inside is not stream but the event. So, I need to do as follow, instead.
peerConn.on('addStream',function(e){
remotevid.src = window.webkitURL.createObjectURL(e.stream);
remotevid.autoplay =true;
});