Hiding legend items do not work in IE 11 and Edge

[dgrechka]

Removing plots causes the following code to execute:

var removeLegendItem = function (i) {
                    var legend = plotLegends[i];
                    plotLegends.splice(i, 1);
                    removeLegend(legend);
                    legend.plot.host.unbind("childrenChanged", childrenChangedHandler);
                    legend.plot.host.unbind("visibleChanged", visibleChangedHandler);
                    if (legend.onLegendRemove) legend.onLegendRemove();
                    legend[0].innerHTML = "";
                    if (isCompact) legend.removeClass("idd-legend-item-compact");
                    else legend.removeClass("idd-legend-item");
                    _jqdiv[0].removeChild(legend[0]);
                    var childDivs = legend.plot.children;
                    childDivs.forEach(function (childPlot) {
                        for (var j = 0, len = plotLegends.length; j < len; j++)
                            if (plotLegends[j].plot === childPlot) {
                                removeLegendItem(plotLegends[j]);
                            }
                    });
                    legend[0].style = "display: none";
                    if (plotLegends.length == 0) divStyle.display = "none";
                };
                for (var i = 0, len = plotLegends.length; i < len; i++)
                    if (plotLegends[i].plot === params.plot) {
                        removeLegendItem(i);
                        break;

The bold line causes error in IE11 and Edge:

SCRIPT5045: Assignment to read-only properties is not allowed in strict mode
idd.js (2177,21)