There might be something bigger wrong with the git-2 eclass.  This build: https://luci-milo.appspot.com/buildbot/chromiumos/moblab-generic-vm-paladin/1689

also shows similar sync errors for other URLs:

ERROR: dev-go/gapi-googleapi-0.0.1-r1::chromiumos failed (unpack phase):
   git-2_update_repo: can't update from https://chromium.googlesource.com/external/github.com/google/google-api-go-client.git

ERROR: dev-go/text-0.0.1::chromiumos failed (unpack phase):
   git-2_update_repo: can't update from https://go.googlesource.com/text.git

The root cause is related to a corrupted git repository (caused either by a job being killed or a network failure).  Moving the corrupted egit2 directory out of the way, allowing it to recreate, resoles the immediate issue:

mv /var/cache/chromeos-cache/distfiles/target/egit-src /var/cache/distfiles/target/egit-src.bak

This has been fixed on cros-beefy97-c2 (covering the Tidus builds).  Will manually apply to any impacted builders we find, with a long term plan to extend the git2-eclass to be clean up the destination directory in the event of a failed fetch.

-- Mike 

Golo host, build112-m2, has also been updated to resolve the corrupted repository.  

-- Mike

Package building has successfully completed for both build configs.  Marking this as complete.

-- Mike