message: refactor(bufferToggle): even smaller
diff: /** @prettier */
  -import { Subscriber } from '../Subscriber';
  import { Observable } from '../Observable';
  import { Subscription } from '../Subscription';
  import { OperatorFunction, SubscribableOrPromise } from '../types';
  -import { lift } from '../util/lift';
  +import { wrappedLift } from '../util/lift';
  import { from } from '../observable/from';
  import { OperatorSubscriber } from './OperatorSubscriber';
  import { noop } from '../util/noop';
  @@ -58,8 +57,7 @@ export function bufferToggle<T, O>(
  closingSelector: (value: O) => SubscribableOrPromise<any>
  ): OperatorFunction<T, T[]> {
  return function bufferToggleOperatorFunction(source: Observable<T>) {
  - return lift(source, function (this: Subscriber<T[]>, source: Observable<T>) {
  - const subscriber = this;
  + return wrappedLift(source, (subscriber, liftedSource) => {
  const buffers: T[][] = [];
  const remove = (buffer: T[]) => {
  @@ -70,15 +68,7 @@ export function bufferToggle<T, O>(
  };
  // Subscribe to the openings notifier first
  - let openNotifier: Observable<O>;
  - try {
  - openNotifier = from(openings);
  - } catch (err) {
  - subscriber.error(err);
  - return;
  - }
  -
  - openNotifier.subscribe(
  + from(openings).subscribe(
  new OperatorSubscriber(
  subscriber,
  (openValue) => {
  @@ -98,24 +88,15 @@ export function bufferToggle<T, O>(
  closingSubscription.unsubscribe();
  };
  - // Get our closing notifier using the open value.
  - let closingNotifier: Observable<any>;
  - try {
  - closingNotifier = from(closingSelector(openValue));
  - } catch (err) {
  - subscriber.error(err);
  - return;
  - }
  -
  // The line below will add the subscription to the parent subscriber *and* the closing subscription.
  - closingSubscription.add(closingNotifier.subscribe(new OperatorSubscriber(subscriber, emit, undefined, emit)));
  + closingSubscription.add(from(closingSelector(openValue)).subscribe(new OperatorSubscriber(subscriber, emit, undefined, emit)));
  },
  undefined,
  noop
  )
  );
  - source.subscribe(
  + liftedSource.subscribe(
  new OperatorSubscriber(
  subscriber,
  (value) => {
  