MenuItem: extend MenuBasePlainItem to support any string indexed properties (#28610)

Author: anna-shakhova

packages/devextreme/js/__internal/grids/grid_core/context_menu/m_context_menu.ts

@@ -109,7 +109,6 @@ export class ContextMenuView extends modules.View {
           }
         },
         onItemClick(params) {
-          // @ts-expect-error
           params.itemData?.onItemClick?.(params);
         },
 

packages/devextreme/js/__internal/ui/context_menu/m_menu_base.edit.strategy.ts

@@ -5,7 +5,6 @@ import PlainEditStrategy from '@ts/ui/collection/m_collection_widget.edit.strate
 
 class MenuBaseEditStrategy extends PlainEditStrategy {
   _getPlainItems(): Item {
-    // @ts-expect-error
     return map(this._collectionWidget.option('items'), function getMenuItems(item) {
       return item.items ? [item].concat(map(item.items, getMenuItems)) : item;
     });

packages/devextreme/js/ui/menu.d.ts

@@ -333,6 +333,8 @@ export interface MenuBasePlainItem extends CollectionWidgetItem {
    * @public
    */
   visible?: boolean;
+
+  [key: string]: any;
 }
 
 /**

packages/devextreme/ts/dx.all.d.ts

@@ -21267,6 +21267,8 @@ declare module DevExpress.ui {
        * [descr:dxMenuBaseItem.visible]
        */
       visible?: boolean;
+
+      [key: string]: any;
     }
     /**
      * [descr:_ui_menu_OptionChangedEvent]