hgweb: pass repo object to revnav construction For compatibility with changelog filtering we need access to the changelog, a simple nodefunc is not sufficient, only the changelog and repo have access the filteredrevs information. For the filerevnav version, we use an unfiltered changelog. Linkrev is currently broken with filtering and we need some failsafe to prevent traceback. This is the same approach as the one used in 518c1403838f. The use of filectx.changectx() allowed the previous code to use the 518c1403838f hack. This changeset may result in an incorrect behaviors, Navigation link may point to missing revision. However this bad navigation generation is much better than a plain crash