message: Accept a value zero in video constraints.
diff: @@ -131,9 +131,9 @@ class Source {
  setVideoConstraints(id, width, height, frameRate) {
  var subscriber = this.getSubscriber(id);
  - var maxWidth = (width && width.max) || -1;
  - var maxHeight = (height && height.max) || -1;
  - var maxFrameRate = (frameRate && frameRate.max) || -1;
  + var maxWidth = (width && width.max !== undefined) ? width.max : -1;
  + var maxHeight = (height && height.max !== undefined) ? height.max : -1;
  + var maxFrameRate = (frameRate && frameRate.max !== undefined) ? frameRate.max : -1;
  subscriber.setVideoConstraints(maxWidth, maxHeight, maxFrameRate);
  }
  