Support Network Inspection

[eugeneo]

Network domain is what Chrome DevTools (and any other interested frontends) use for inspecting the HTTP and WS traffic in the browser. This document provides some insight into Chrome DevTools UI and here is a description of the protocol for obtaining that data.

We propose to introduce a Node specific agent that would expose the same (or subset) of this protocol to enable the UI. It does not seem possible to share the implementation between Blink and Node.js.

This agent would also introduce an API for the modules to report the events. E.g. WebSocket modules should be able to notify the agent when WS frames are sent or received.