Anton Shestakov <av6@dwimlabs.net> [Mon, 11 Feb 2019 21:33:02 +0800] rev 4399
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().