fix(igxHierarchicalGrid): stopPropagation on expander click.

Author: MKirova

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

@@ -1,4 +1,4 @@
-<div (click)="toggle()" class="igx-grid__hierarchical-expander" [tabIndex]="tabindex" *ngIf="hasChildren" #expander>
+<div (click)="expanderClick($event)" class="igx-grid__hierarchical-expander" [tabIndex]="tabindex" *ngIf="hasChildren" #expander>
         <ng-container *ngTemplateOutlet="iconTemplate; context: { $implicit: this }">
         </ng-container>
 </div>

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

@@ -82,13 +82,21 @@ export class IgxHierarchicalRowComponent extends IgxRowComponent<IgxHierarchical
         return this.grid && this.grid.highlightedRowID === this.rowID;
     }
 
+    /**
+    * @hidden
+    */
+    protected expanderClick(event) {
+        event.stopPropagation();
+        this.toggle();
+    }
+
     /**
      * Toggles the hierarchical row.
      * ```typescript
      * this.grid1.rowList.first.toggle()
      * ```
      */
-    public toggle(event?) {
+    public toggle() {
         if (this.added) {
             return;
         }