perf: update perfindex to be more realistic
The previous code was creating a revlog manually, we now use the actual
`localrepo` method to create it.
We have to jump though extra hops to work around the impact of filecache.
#require docutils gettext
$ $TESTDIR/check-gendoc de
checking for parse errors
Die Dateien werden dem Projektarchiv beim n\xc3\xa4chsten \xc3\x9cbernehmen (commit) hinzugef\xc3\xbcgt. Um dies vorher r\xc3\xbcckg\xc3\xa4ngig zu machen, siehe:hg:`forget`. (esc)
warning: please have a space before :hg: