The Chromium build instructions are very clear on this: https://www.chromium.org/developers/how-tos/api-keys

> Note that the keys you have now acquired are not for distribution purposes and must not be shared with other users.

> Many of the Google APIs used by Chromium code are specific to Google Chrome and not intended for use in derived products. In the API Console (http://developers.google.com/console) you may be able to purchase additional quota for some of the APIs listed above. For APIs that do not have a "Pricing" link, additional quota is not available for purchase.

The notice has been there since 2013, when the page was first archived:

https://web.archive.org/web/20131211101458/https://www.chrom...