[merge] don't treat enoent from readdir as indicating eof

[Bundle Buggy]

Bundle Buggy has detected this merge request.

For details, see: 
http://bundlebuggy.aaronbentley.com/project/bzr/request/%3Ce01316480810062217y541e3f1blcb998299876e9317%40mail.gmail.com%3E
Project: Bazaar