code: function getCanvasSize (canvasEl, embedded, maxSize, isVR) {
    if (embedded) {
      return {
        height: canvasEl.parentElement.offsetHeight,
        width: canvasEl.parentElement.offsetWidth
      };
    }
    return getMaxSize(maxSize, isVR);
  }
docs: Return the canvas size where the scene will be rendered.
  Will be always the window size except when the scene is embedded.
  The parent size (less than max size) will be returned in that case.
  
  @param {object} canvasEl - the canvas element
  @param {boolean} embedded - Is the scene embedded?
  @param {object} max - Max size parameters
  @param {boolean} isVR - If in VR