apply --cached (as used by add -p) should accept creation and deletion
patches to intent-to-add paths in the index. apply --index, however,
should always fail because an intent-to-add path never matches the
worktree (by definition).
Based-on-patch-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Raymond E. Pasco <ray@ameretat.dev>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
