fix(excel search): error onFocus 16.1.x #13743 (#13744)

Co-authored-by: Hristiana Hristova <[email protected]>

Author: GrblackStar

projects/igniteui-angular/src/lib/grids/filtering/excel-style/excel-style-search.component.ts

@@ -653,11 +653,13 @@ export class IgxExcelStyleSearchComponent implements AfterViewInit, OnDestroy {
 
     protected onFocus() {
         const firstIndexInView = this.virtDir.state.startIndex;
-        this.focusedItem = {
-            id: this.getItemId(firstIndexInView),
-            index: firstIndexInView,
-            checked: this.virtDir.igxForOf[firstIndexInView].isSelected
-        };
+        if (this.virtDir.igxForOf.length > 0) {
+            this.focusedItem = {
+                id: this.getItemId(firstIndexInView),
+                index: firstIndexInView,
+                checked: this.virtDir.igxForOf[firstIndexInView].isSelected
+            };
+        }
         this.setActiveDescendant();
     }