Empty unstaged changes shown on rename

[proski]

Run this file in an empty directory to reproduce the bug:

#! /bin/sh

rm -rf .git
rm -f file*
git init
echo data >file1
git add file1
git commit -m "commit1"
echo data >file2
git add file2
git rm file1

Run tig after that script. It will show "Unstaged changes" in the change list, but pressing Enter on that entry won't have any effect. It is important for reproducing the bug that file1 and file2 have the same contents.