Add RUM data

One thing I've been thinking a lot about is how to incorporate RUM data into LH reporting.

LH suggests many ideal targets for developers to hit, in particular perf numbers. Incorporating real-world data from sources like **httparchive** and **caniuse** could be a helpful barometer for devs to see where they're landing.

Where RUM data would be useful:

- see how your app stacks up against other top sites. In theory, the top sites are well built and are showcases of the web platform.
- help developers prioritize fixing perf issues.
- are the ideal numbers LH suggests reasonable?
- Analytics: what are the most important things I should address for _my_ users? e.g. have users input an **Google Analytics** ID and use the Google Analytics Reporting API to compare a run with the app's actual user base
- caniuse: "LH told me to use this new API, but it has 50% browser support". See https://github.com/GoogleChrome/lighthouse/issues/704

For httparchive data, I threw together a webservice on App Engine that always pulls from the latest snapshot of httparchive's bigquery dumps. Turns out they didn't have a JSON API.

endpoint: https://lighthouse-viewer.appspot.com/data
demo: https://lighthouse-viewer.appspot.com/

I also have a node script that we could run during report generation. The benefit of the webservice is that anyone can use it and it's highly cached.

POC UI:


There's a lot we could do in this space. I'm interested in hearing everyone's thoughts. Need some UI explorations. We could annotate certain audits (like the screenshot) or have an entire new section for RUM stuff.

@paulirish @igrigorik