Kevin Bullock <kbullock@ringworld.org> [Thu, 01 Aug 2013 21:43:14 -0500] rev 19523
bookmarks: pull --update updates to active bookmark if it moved (issue4007)
This makes `hg pull --update` behave the same wrt the active bookmark as
`hg pull && hg update` does as of 2096e025a728. A helper function,
bookmarks.calculateupdate, is added to prevent code duplication between
postincoming and update.