getUserMedia shim/polyfill via: https://github.com/webrtc/adapter
npm install gumadapterCopyrights goes to:
* https://github.com/webrtc/adapter/blob/master/LICENSE.md
 
> navigator.getUserMedi is upgraded into promises based API: navigator.mediaDevices.getUserMedia.
>
> This shim/polyfill merely helps handling cross-browser issues.
* https://github.com/muaz-khan/gumadapter/releases
``html`
It is suggested to link specific release:
* https://github.com/muaz-khan/gumadapter/releases
E.g.
`html`
`javascript
function successCallback(stream) {
video.srcObject = stream;
}
function errorCallback(error) {
// maybe another application is using the device
}
var mediaConstraints = { video: true, audio: true };
navigator.mediaDevices.getUserMedia(mediaConstraints).then(successCallback).catch(errorCallback);
``