Forward built-in logs to the Tracing Console

[janodvarko]

There are many logs in the native tools and it would be great if those also appear in the tracing console.

Native tools use:

1. a pref to make those logs visible: "devtools.debugger.log"
2. and system dump() to display the result in the system console.

See e.g.
https://mxr.mozilla.org/mozilla-central/source/browser/devtools/debugger/debugger-controller.js#2296

Any tips how we could do this?

Honza