The position of Frozen columns is incorrect if .hideIndex() is used.

Hi,

While working on my requirement I observed that the position of the frozen column is not set correctly if your index number column is hidden. I found the solution, posted it below.

obj.updateFreezePosition = function() {
            scrollLeft = obj.content.scrollLeft;
            var width = 0;
            if (scrollLeft > 50) {
                for (var i = 0; i < obj.options.freezeColumns; i++) {
                    if (i > 0) {
                        width += parseInt(obj.options.columns[i-1].width);
                    }
                    obj.headers[i].classList.add('jexcel_freezed');
                    obj.headers[i].style.left = width + 'px';
                    for (var j = 0; j < obj.rows.length; j++) {
                        if (obj.rows[j] && obj.records[j][i]) {
                            var indexColumnWidth = (obj.table.classList.contains('jexcel_hidden_index') ? 1 : 51)
                            var shifted = (scrollLeft + (i > 0 ? obj.records[j][i-1].style.width : 0)) - indexColumnWidth + 'px';
                            obj.records[j][i].classList.add('jexcel_freezed');
                            obj.records[j][i].style.left = shifted;
                        }
                    }
                }
            } else {
                for (var i = 0; i < obj.options.freezeColumns; i++) {
                    obj.headers[i].classList.remove('jexcel_freezed');
                    obj.headers[i].style.left = '';
                    for (var j = 0; j < obj.rows.length; j++) {
                        if (obj.records[j][i]) {
                            obj.records[j][i].classList.remove('jexcel_freezed');
                            obj.records[j][i].style.left = '';
                        }
                    }
                }
            }

            // Place the corner in the correct place
            obj.updateCornerPosition();
        }

Start with the updateFreezePosition entry point shown in the issue and reproduce the frozen-column behavior with .hideIndex() enabled. Compare the column positions when the index is visible and hidden, using the proposed logic as context; the work is done when frozen columns and the corner remain correctly positioned in both cases.