[PATCH 3/4] fast-export: don't parse all the commits

We don't need the parsed objects at this point, merely the information
that they have marks.

Seems to be three times faster in my setup with lots of objects.

Signed-off-by: Felipe Contreras <redacted>
---
 builtin/fast-export.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/builtin/fast-export.c b/builtin/fast-export.c
index a5b8da8..3c5a701 100644
--- a/builtin/fast-export.c
+++ b/builtin/fast-export.c

@@ -636,7 +636,7 @@ static void import_marks(char *input_file)
 			/* only commits */
 			continue;
 
-		object = parse_object(sha1);
+		object = lookup_unknown_object(sha1);
 
 		if (object->flags & SHOWN)
 			error("Object %s already has a mark", sha1_to_hex(sha1));

-- 
1.8.3.rc0.401.g45bba44