fix(grid): restore trailing scroll emission so top rows aren't lost after fast scroll - 21.2.x#17460

Zneeky wants to merge 3 commits into

21.2.xIgniteUI/igniteui-angular:21.2.xfrom

aahmedov/fix-grid-scroll-trailing-21.2.xIgniteUI/igniteui-angular:aahmedov/fix-grid-scroll-trailing-21.2.xCopy head branch name to clipboard