Following up on
https://groups.google.com/d/topic/jenkinsci-dev/xxGlx_8KNdg/discussion (I'm sorry, I could not find a way to add a CC to an existing thread, so I had to start a new one).
It seems that the project has been mostly abandoned (@jrluis is copied here). The last commit was Feb 2017, and there are 4 outstanding pull requests ranging from Sept 2017 - Jul 2018 (5 including mine from today).
As of the Google OAuth plugin update v0.8, the GCloud SDK plugin no longer works. The only user-accessible solution is to downgrade the OAuth plugin to v0.7.
Barring any objections from João, the original maintainer since 2015, I'd like to formally request commit access to help clean up the plugin and get it back to a usable state. I'm already a member of the jenkins-ci org on github.
My Jenkins account: jhansche
Thanks,
Joe