Engine, thanks for the news. Good to know.
For recent prior discussion of the "Speed" metric, discussing among other things the various possible sources for the Speed data, and possibly with a broader view, see... PageSpeed Insights "Speed" Metric https://www.webmasterworld.com/google/4882265.htm
The Chrome User Experience Report is powered by real user measurement of key user experience metrics across the public web, aggregated from users who have opted-in to syncing their browsing history, have not set up a Sync passphrase, and have usage statistic reporting enabled....
I've got to confess this all does not yet come trippingly off the tongue. If anyone has a really intuitive feeling for the available data sets and interlocking tools, I'd love to see them summarized.