CxxModule exports method bar() that will send JS event to simulate AppState changes

HelloCxxModule.cpp

auto HelloCxxModule::getMethods() -> std::vector<Method> {
  return {
      Method("bar",
             [this]() {
               if (auto reactInstance = getInstance().lock()) {
                 reactInstance->callJSFunction(
                     "RCTDeviceEventEmitter", "emit",
                     folly::dynamic::array(
                         "appStateDidChange",
                         folly::dynamic::object("app_state", "active")));
               }
             }),
  };
}