These are all done by legitimate actions supported by git ... it just turns out that if you have a process backed by a central canonical repository, you really don't want your source disappearing out from under you. "I might have pushed back most of our repo" is not an acceptable level of support :-)
We were able to find a mostly complete repo, disable the Eclipse Foundation commit hook and push back the repo. We are discussing ways to limit this kind of damage in the future. See
- Bug 362076 - Better policy to guard against deleting all branches and tags from our public repos
- Bug 362361 - Better policy ... enforce receive.denyDeletes = true
- Bug 362363 - Better policy ... provide hooks to allow a committer to delete
/branchname branches