svnrepo: kludge to work around hash changes between stupid and replay in hg 1.9 This causes every commit to get a new manifest, just like hg 1.8 and earlier. It also fixes some problems where stupid and replay produced different hashes under 1.9, which is the primary motivation for preserving the old behavior. Hopefully some day we can back this out and be smarter about stupid mode, or can stupid mode entirely in favor of some smarter validations in 'hg svn verify'.