code: function (prop, value) {
        this.lowerCanvasEl[prop] = value;
        this.lowerCanvasEl.style[prop] = value + 'px';
  
        if (this.upperCanvasEl) {
          this.upperCanvasEl[prop] = value;
          this.upperCanvasEl.style[prop] = value + 'px';
        }
  
        if (this.wrapperEl) {
          this.wrapperEl.style[prop] = value + 'px';
        }
  
        this[prop] = value;
  
        this.calcOffset();
        this.renderAll();
  
        return this;
      }
docs: Helper for setting width/height
  @private
  @method _setDimensions
  @param {String} prop property (width|height)
  @param {Number} value value to set property to
  @return {fabric.Canvas} instance
  @chainable true