obshistory: omit keyword arguments with default values in patch.diffui() calls d4c9eebdd72d made that function not take "relroot" and "prefix" anymore, and instead expect "pathfn". These two chunks of code in this patch simply generate patches for obslog -p and they broke because they tried to provide default values for "prefix" and "relroot" for no apparent reason (and also for "changes"). Let's instead rely on defaults of patch.diffui().

# utility to setup pythonpath to point into the tested repository

export SRCDIR=`dirname $TESTDIR`
if [ -n "$PYTHONPATH" ]; then
    export HGTEST_ORIG_PYTHONPATH=$PYTHONPATH
    export PYTHONPATH=$SRCDIR:$PYTHONPATH
else
    export PYTHONPATH=$SRCDIR
fi