Wojciech Lopata <lopek@fb.com> [Mon, 26 Aug 2013 16:50:31 -0700] rev 19629
bundlerevlog: extract 'baserevision' method
This makes possible to use bundlerevlog class with subclasses of revlog
that override revlog's 'revision' method. In particular this change is necessary
to implement manifest compression, as it allows extension to replace manifest
class and override 'revision' method there.