DropDownEditor, DropDownList, SelectBox, TagBox, DropDownBox: convert into ES6 class (DevExpress#29165)

Author: EugeniyKiyashko

packages/devextreme/js/__internal/core/utils/m_array.ts

@@ -27,7 +27,7 @@ export const getIntersection = function (firstArray, secondArray) {
   });
 };
 
-export const removeDuplicates = function (from = [], toRemove = []) {
+export const removeDuplicates = function (from = [], toRemove: any[] = []) {
   const toRemoveMap = createOccurrenceMap(toRemove);
   return from.filter((value) => {
     const occurrencesCount = toRemoveMap.get(value);

packages/devextreme/js/__internal/core/utils/m_position.ts

@@ -1,7 +1,7 @@
 import config from '@js/core/config';
 import { isWindow } from '@js/core/utils/type';
 
-const getDefaultAlignment = (isRtlEnabled) => {
+const getDefaultAlignment = (isRtlEnabled?: boolean): 'left' | 'right' => {
   const rtlEnabled = isRtlEnabled ?? config().rtlEnabled;
 
   return rtlEnabled ? 'right' : 'left';

packages/devextreme/js/__internal/core/widget/widget.ts

@@ -54,7 +54,7 @@ class Widget<
 
   private readonly _feedbackShowTimeout = 30;
 
-  private _contentReadyAction?: ((event?: Record<string, unknown>) => void) | null;
+  _contentReadyAction?: ((event?: Record<string, unknown>) => void) | null;
 
   private _keyboardListenerId?: string | null;
 

packages/devextreme/js/__internal/ui/date_box/m_date_box.base.ts

@@ -57,7 +57,7 @@ const STRATEGY_CLASSES = {
   CalendarWithTime,
   List,
 };
-
+// @ts-expect-error
 const DateBox = DropDownEditor.inherit({
 
   _supportedKeys() {