UserAgent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.77 Safari/537.36

Steps to reproduce the problem:
Using the following console code:
function sampleCode() {
  var mediaRecorder;

  navigator.mediaDevices.getUserMedia({
      audio: true,
      video: true
    })
    .then(function(stream) {
      window.stream = stream;
    })
    .then(function() {
      mediaRecorder = new MediaRecorder(window.stream, {
        "mimeType": "video/webm;codecs=vp8"
      });

    })
    .catch(function(err) {
      throw new Error(err.toString());
    });
}

1) Open Firefox, run the sampleCode method, accept the prompts
2) Open Chrome, run the sampleCode method, prompts show
3) Accept the prompts, no errors thrown even though the camera is in use by another application

What is the expected behavior?
Should get some error so the end user can be notified that the webcam is possibly in use by another application

What went wrong?
No errors were thrown, and if the steps are taken to preview the webcam feed, it results in a black screen

Did this work before? N/A 

Does this work in other browsers? Yes

Chrome version: 70.0.3538.77  Channel: stable
OS Version: 10.0
Flash Version: 

I think this is a regression, but it's difficult to test old versions of chrome (while accessing the webcam) with my setup.