listener: extract active_tcp_socket and active_stream_listener_base

[lambdai]

Commit Message:

Split from #16947
Extract ActiveTcpSocket from ActiveTcpListener.
Extract a base class ActiveStreamListener from ActiveTcpListener.

Additional Description:
The new base class owns the the active sockets that drive itself through the listener filters.
After the active socket passes all the listener filters, a server connection is created. As a derived listener,
ActiveTcpListener overrides newActiveConnection to take the ownership of that server connection.

Risk Level: LOW
Testing:
Docs Changes:
Release Notes:
Platform Specific Features:
[Optional Runtime guard:]
[Optional Fixes #Issue]
[Optional Deprecated:]
[Optional API Considerations:]

[mattklein123]

Check CI?

/wait

[lambdai]

Ahrr, Add a setting to my vscode

[mattklein123]

Can you summarize what code you actually changed vs. moved? What do I need to review?

/wait-any

[lambdai]

Can you summarize what code you actually changed vs. moved? What do I need to review?

/wait-any

Sure.

1. active_tcp_socket.{h,cc} It's a pure move other than referring a parent class of ActiveTcpListener.
2. ActiveStreamListenerBase is the new extracted parent class of ActiveTcpListener. Sitting in it's new file active_stream_listener_base.{h, cc}. Its interface a strict subset of the previous ActiveTcpListener. The only exception is newActiveConnection that is designed to be overridden by ActiveTcpListener.
   Particularly, no data member is added to ActiveTcpListener+ActiveStreamListenerBase. All the functions have the exact semantic before the refactor.

The goal is to avoid duplicating the ActiveTcpListener when a ActiveInternalListener is added.

Without the context of the above goal, this PR should be small win regarding the achievement of less coupling between ActiveTcpSocket and ActiveTcpListener.

[mattklein123]

Thanks, generally makes sense with some random comments.

/wait

[lambdai]

fixing conflict
/wait

[mattklein123]

OK LGTM pending the other open comment thread about moving to protected, thanks.

/wait

[lambdai]

OK LGTM pending the other open comment thread about moving to protected, thanks.

/wait

I had the illusion it is done.

Now I am trying to move to protected and I realize it was public even before this PR.

This things I am doing is:

1. declare it protected.
2. add const getter. it is for test only, I can take a look how to avoid using it in the test.
3. add a remove method in this class to mutate this list.

[mattklein123]

Thanks!