filectx: use ctx.size comparisons to speed up ctx.cmp Comparing sizes is cheaper than comparing file contents, as it does not involve reading the file on disk or from the filelog. It is however not always possible: some extensions, or encode filters, change data when extracting it to the working directory. [ original upstream description ]

Merge with stable

Code cleanup - move preselection of expansion candidates for rollback and record into helper function - same overwrite order in rollback and record: 1. modified, 2. added - self.wlock() inside kwrepo class instead of repo.wlock()