Well, as luck have it, Google don't let individuals be individuals if they work for Google, so anything under github.com/google or github.com/google-research could be a weekend hack project from an individual with zero association to Google itself, or the most supported project at Google, everything always go under Google's name if you work for Google. Basically, free-time as the typical person understands it, does not exists if you work for Google.
The disclaimer in the bottom of these project makes the distinction a bit clear, once you got to the bottom of the README:
> Disclaimer This is not an officially supported Google product.
The disclaimer in the bottom of these project makes the distinction a bit clear, once you got to the bottom of the README:
> Disclaimer This is not an officially supported Google product.