merge-recursive: Fix recursive case with D/F conflict via add/add conflict

When a D/F conflict is introduced via an add/add conflict, when
o->call_depth > 0 we need to ensure that the higher stage entry from the
base stage is removed.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

merge-recursive.c

@@ -1466,6 +1466,8 @@ static int process_df_entry(struct merge_options *o,
 			       "Adding %s as %s",
 			       conf, path, other_branch, path, new_path);
 			update_file(o, 0, sha, mode, new_path);
+			if (o->call_depth)
+				remove_file_from_cache(path);
 			free(new_path);
 		} else {
 			output(o, 2, "Adding %s", path);

t/t6036-recursive-corner-cases.sh

@@ -509,7 +509,7 @@ test_expect_failure 'merge of D & E1 fails but has appropriate contents' '
 	test $(git rev-parse :2:a) = $(git rev-parse B:a)
 '
 
-test_expect_failure 'merge of E1 & D fails but has appropriate contents' '
+test_expect_success 'merge of E1 & D fails but has appropriate contents' '
 	get_clean_checkout E1^0 &&
 
 	test_must_fail git merge -s recursive D^0 &&
@@ -539,7 +539,7 @@ test_expect_success 'merge of D & E2 fails but has appropriate contents' '
 	test -f a~HEAD
 '
 
-test_expect_failure 'merge of E2 & D fails but has appropriate contents' '
+test_expect_success 'merge of E2 & D fails but has appropriate contents' '
 	get_clean_checkout E2^0 &&
 
 	test_must_fail git merge -s recursive D^0 &&