convert: make contents of "extra" dict available from sources, for sinks.
This breaks hash preservation for hg->hg conversion, as each converted
change gets a convert_revision item added to its extra dict. Ugh.
#!/bin/sh
# http://www.selenic.com/mercurial/bts/issue352
"$TESTDIR/hghave" eol-in-paths || exit 80
hg init foo
cd foo
A=`printf 'he\rllo'`
echo foo > "$A"
hg add
hg ci -A -m m
rm "$A"
echo foo > "hell
o"
hg add
hg ci -A -m m
echo foo > "$A"
hg debugwalk
exit 0