bug#54034: 29.0.50; Diff prettify broken for empty files

[Stefan Monnier]

> I found one unhandled case. When a diff changes a file mode, like in the
> following:
>
>     diff --git a/argos/session.py b/argos/session.py
>     old mode 100755
>     new mode 100644

I just pushed a change for that as well.
Of course, there's always the problem that this prettification
hides info, so there's a tension here.


        Stefan