@lanodan This is mostly an artifact of the fact that Google doesn't have good git repo management internally from what I can tell.
There's a reason the joke for "how do I contribute to Chromium" is "well, the easiest path is to become a Google employee."
I do know someone who did precisely that: Became a Google employee simply to shepherd a change through code review that had been outstanding for two years, get it merged and committed, and then **left** Google to go back to the literal sheep herding they had been doing previously as a full time job.