If you've pulled in the last couple hours, you likely got the revision:
This revision was generated by the "resolve pull request" mechanism that Bitbucket has just added. Unfortunately, it added a new branch in doing so. Normally this isn't a problem, except that the new branch name is 'default' which happens to be a special name for branches that could cause issues down the road with yt. I've stripped the revision.
If you have pulled in the last couple hours, please issue this command:
hg strip fefad26500f2
on your repository; if you have already pushed to a fork on bitbucket, use their admin page to strip out that bad revision. I request strongly that you *not* push this revision to the main repository.
Sorry about the mess. I've filed a ticket with BB because this seems like a pretty clear bug.