code: function autoAddLegendMargin() {
  			switch(options.legendVerticalPosition) {
  			case "top":
  				options.legendMargin[2] = parent.DEFAULT_LEGEND_MARGIN;
  				break;
  			case "bottom":
  				options.legendMargin[0] = parent.DEFAULT_LEGEND_MARGIN;
  				break;
  			case "middle":
  			case "center":
  				options.legendMargin[options.legendHorizontalPosition === "right" ? 3 : 1] = parent.DEFAULT_LEGEND_MARGIN;
  			}
  		}
docs: If not specified, add some margin around the legend depending on its position
  
  @return void