refactor statistics

[boneskull]

Stat gathering (fails, passes, errors, duration) is too closely coupled to the reporter. The reporter shouldn't be the single source of truth for this information, yet it is. Statistics should be queried by the reporters instead of just dumped into the base reporter. The result may be as simple as an abstraction between the runner and reporter.

This makes it difficult to modify the stats we gather, or how we gather them.

related: #3223, #3250

[Nokel81]

I will take a look into this do you know of a good place to start?

[craigtaub]

@Nokel81 been a while, any progress? Im happy to look at this too, think I know what needs to be done.

[craigtaub]

@boneskull PR open, be interested to hear if this is/not the kind of abstraction you imagined.