There was a pull request merged a few minutes ago, by someone whose username suggests that they are also the first named author on the Google blog post.
Possible that it was in internal limbo for a while, and that the decision to release it as a community project actually may bring it back to life, even among Google staff.
(Never worked in Google, but it may be easier for interested employees to contribute to external open-source projects than internal projects with no resource allocation.)
https://github.com/e2email-org/e2email/commit/434f99c66efe49...
Hopefully there's more to come! :-P