I don't know what the bigger WTF is here, the fact that SVN crashes this badly with files that have the same sha1 hash, that the WebKit team are still using SVN, or that their solution was to zip the offending files so that they can continue using SVN
The biggest is that they tested it on the WebKit repo, not a specific testing repo.
As I understand it they weren't testing the repo. They were checking in test code that was supposed to check if webkit breaks with those files. Then that became irrelevant because it broke their repo instead.