However, there were 767 unique authors who committed code direct to chromium in the last week:
https://github.com/chromium/chromium/pulse
And I would guess the Chrome team is probably 3-5x that, since many people may not be working on code, may not commit directly, or might be working on big things on branches and didn't commit anything this week. Also, that doesn't count work on external dependencies, which are counted as "autoroll bots".