message: work for : extend method signature surveyLocalization.getString
diff: @@ -7,9 +7,7 @@ export var surveyLocalization = {
  localeNames: <{ [index: string]: any }>{},
  supportedLocales: <Array<any>>[],
  get currentLocale() {
  - return this.currentLocaleValue === this.defaultLocaleValue
  - ? ""
  - : this.currentLocaleValue;
  + return this.currentLocaleValue === this.defaultLocaleValue ? "" : this.currentLocaleValue;
  },
  set currentLocale(val: string) {
  if (val === "cz") val = "cs";
  @@ -25,15 +23,14 @@ export var surveyLocalization = {
  getLocaleStrings(loc: string): any {
  return this.locales[loc];
  },
  - getCurrentStrings(): any {
  - var loc = this.currentLocale
  - ? this.locales[this.currentLocale]
  - : this.locales[this.defaultLocale];
  + getCurrentStrings(locale?: string): any {
  + let loc = locale && this.locales[locale];
  + if (!loc) loc = this.currentLocale ? this.locales[this.currentLocale] : this.locales[this.defaultLocale];
  if (!loc) loc = this.locales[this.defaultLocale];
  return loc;
  },
  - getString: function (strName: string) {
  - var loc = this.getCurrentStrings();
  + getString: function (strName: string, locale: string = null) {
  + var loc = this.getCurrentStrings(locale);
  if (!loc[strName]) loc = this.locales[this.defaultLocale];
  var result = loc[strName];
  if (result === undefined) {
  