It works like this. Google has an "open source office". When you open source code at Google, it's either a product, or it isn't. Even if it's not a product (which has its own extra set of launch procedures), it's possible to open source it. It's still a Google-owned thing, but not a "product". Google ownership does not necessarily mean it's a product, but it still requires the copyright stamp and the CLA.

If it's easier, just drop the word "official". It's not a Google product- IE, a saleable or free service that google provides to customers- but rather just a thing Google put out in the world, subject to the rules that Google applies.