sparse: fix debugrebuilddirsate when narrow extension is enabled
dirstate wrapping in narrow extension converts the manifest object to a list. So
let's assume we get a list of files in sparse extension.
Differential Revision: https://phab.mercurial-scm.org/D5481
#require serve
$ hg clone http://localhost:$HGPORT/ copy
abort: * (glob)
[255]
$ test -d copy
[1]
$ "$PYTHON" "$TESTDIR/dumbhttp.py" -p $HGPORT --pid dumb.pid
$ cat dumb.pid >> $DAEMON_PIDS
$ hg clone http://localhost:$HGPORT/foo copy2
abort: HTTP Error 404: * (glob)
[255]
$ killdaemons.py