Google doesn't support it in any way (=not a product), it's just something the author made during her time at Google internally (=it has Google copyright) that's now open-sourced.
A Googler once told me that any code he writes during his employment with Google belongs to Google copyright-wise.
If they want to open source anything they have to ask Google for permission. It doesn't have to be hosted under the Google GitHub organization though (take Camlistore[1] as an example, although their primary repository is still hosted at googlesource.com).
This also means that if you want to contribute code to an open source project started by a Googler you will have to sign the Google CLA.
I don't think that's true for every project, as I have contributed to an open-source project[1] started by a Googler, and never had to sign a CLA, nor is the project hosted under the Google Github org.
TL;DR: Google's employment agreement means Google owns the copyright, which is what you see here. That doesn't mean we are endorsing the repo or making any claims to its importance.
https://twitter.com/GalaxyKate/status/925159463807361024