message: refactor: Fix broken while loop in canReportError
  https://github.com/ReactiveX/rxjs/pull/5729/files\#r489645413
diff: @@ -494,9 +494,10 @@ function getPromiseCtor(promiseCtor: PromiseConstructorLike | undefined) {
  export function canReportError(subscriber: Subscriber<any>): boolean {
  while (subscriber) {
  const { closed, destination, isStopped } = subscriber as any;
  - return closed || isStopped
  - ? false
  - : (destination && destination instanceof Subscriber ? (subscriber = destination) : (subscriber = null!), true);
  + if (closed || isStopped) {
  + return false;
  + }
  + subscriber = destination && destination instanceof Subscriber ? destination : null!;
  }
  return true;
  }
  