chore(*): Fix reflow issue in Chrome another way so it does not break Firefox.

Author: MKirova

projects/igniteui-angular/src/lib/directives/for-of/for_of.directive.ts

@@ -1195,8 +1195,6 @@ export class IgxForOfDirective<T> implements OnInit, OnChanges, DoCheck, OnDestr
             }
         }
         if (this.igxForScrollOrientation === 'vertical') {
-            // reset width to force reflow.
-            this.scrollComponent.nativeElement.style.width = '';
             this.scrollComponent.nativeElement.style.height = parseInt(this.igxForContainerSize, 10) + 'px';
             this.scrollComponent.size = this._calcHeight();
             if ( this.scrollComponent.size <= parseInt(this.igxForContainerSize, 10)) {

projects/igniteui-angular/src/lib/directives/for-of/virtual.helper.component.ts

@@ -40,7 +40,7 @@ export class VirtualHelperComponent extends VirtualHelperBaseDirective implement
         document.body.appendChild(div);
         const scrollWidth = div.offsetWidth - div.clientWidth;
         document.body.removeChild(div);
-        return scrollWidth;
+        return scrollWidth ? scrollWidth + 1 : 0;
     }
 
 }