Follow-up from "Draft: Resolve "heap-use-after-free and invalid vptr on PingCheckMgr destruction""

The following discussion from !2197 (merged) should be addressed:

• @andrei started a discussion: (+3 comments)

  To keep the members alive, they can be added to a lambda function which uses a smart pointer to capture the object, but does not use it. It then must be added to the IOService queue using the post function.

  I would take the shared_from_this alternative anytime if it gets rid of the posts.

  If you think that it is too much work for now although it shouldn't be, we can create a ticket, but can you at least add comments to say that they are posted only for extending lifetime?

  Core:

  +    getIOService()->post(std::bind(f, queue_mgr_));
  +        io_service_->post(std::bind(f, timer_));
  +    io_service_->post(std::bind(f, timer_));
  +    io_service_->post(std::bind(f, timer_));
  +    io_service_->post(std::bind(f, timer_, tcp_socket_, tls_socket_));

  Premium:

  +        main_io_service_->post(std::bind(f, expiration_timer_, channel_));