t3404: "rebase -i" gets broken when insn sheet uses CR/LF line endings

Based on a bug report by Chad Boles.
Signed-off-by: NJohannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

t/t3404-rebase-interactive.sh

@@ -1240,4 +1240,16 @@ test_expect_success 'static check of bad SHA-1' '
 	test E = $(git cat-file commit HEAD | sed -ne \$p)
 '
 
+test_expect_failure 'editor saves as CR/LF' '
+	git checkout -b with-crlf &&
+	write_script add-crs.sh <<-\EOF &&
+	sed -e "s/\$/Q/" <"$1" | tr Q "\\015" >"$1".new &&
+	mv -f "$1".new "$1"
+	EOF
+	(
+		test_set_editor "$(pwd)/add-crs.sh" &&
+		git rebase -i HEAD^
+	)
+'
+
 test_done