Merge branch 'master' into resolve-merge-conflict

Author: Lipata

projects/igniteui-angular/src/lib/grids/grid/grid.component.html

@@ -115,6 +115,7 @@
             let-rowIndex="index" [igxForScrollOrientation]="'vertical'" [igxForScrollContainer]='verticalScroll'
             [igxForContainerSize]='calcHeight'
             [igxForItemSize]="hasColumnLayouts ? rowHeight * multiRowLayoutRowSize + 1 : renderedRowHeight"
+            [igxForTrackBy]='trackChanges'
             #verticalScrollContainer (onChunkPreload)="dataLoading($event)">
             <ng-template
                 [igxTemplateOutlet]='getRowTemplate(rowData)'

projects/igniteui-angular/src/lib/grids/grid/grid.component.ts

@@ -688,6 +688,16 @@ export class IgxGridComponent extends IgxGridBaseDirective implements GridType,
         }
     }
 
+    /**
+     * @hidden
+     */
+    public trackChanges(index, rec) {
+        if (rec.detailsData !== undefined) {
+            return rec.detailsData;
+        }
+        return rec;
+    }
+
     public detailsKeyboardHandler(event, rowIndex, container) {
         const colIndex = this.selectionService.activeElement ? this.selectionService.activeElement.column : 0;
         const shift = event.shiftKey;