chore(*): Move logic to target only hierarchical grid.

Author: MKirova

projects/igniteui-angular/src/lib/grids/grid-base.directive.ts

@@ -2735,9 +2735,7 @@ export class IgxGridBaseDirective extends DisplayDensityBase implements
         this.columnList.changes
             .pipe(takeUntil(this.destroy$))
             .subscribe((change: QueryList<IgxColumnComponent>) => {
-                Promise.resolve().then(() => {
-                    this.onColumnsChanged(change);
-                });
+                this.onColumnsChanged(change);
             });
     }
 

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

@@ -415,12 +415,14 @@ export class IgxHierarchicalGridComponent extends IgxHierarchicalGridBaseDirecti
     }
 
     protected onColumnsChanged(change: QueryList<IgxColumnComponent>) {
-        this.updateColumnList();
-        const cols = change.filter(c => c.gridAPI.grid === this);
-        if (cols.length > 0 || this.autoGenerate) {
-            this.columnList.reset(cols);
-            super.onColumnsChanged(this.columnList);
-        }
+        Promise.resolve().then(() => {
+            this.updateColumnList();
+            const cols = change.filter(c => c.gridAPI.grid === this);
+            if (cols.length > 0 || this.autoGenerate) {
+                this.columnList.reset(cols);
+                super.onColumnsChanged(this.columnList);
+            }
+        });
     }
 
     private updateColumnList(recalcColSizes = true) {