fix(grid): address null TypeError on focusing a grid with no data and column headers - 19.2.x#16522

kacheshmarova merged 2 commits into19.2.xIgniteUI/igniteui-angular:19.2.xfrom

bpachilova/ariaHidden-header-groups-fix-16517-19.2.xIgniteUI/igniteui-angular:bpachilova/ariaHidden-header-groups-fix-16517-19.2.xCopy head branch name to clipboard