cache.h: add repository argument to oid_object_info

Add a repository argument to allow the callers of oid_object_info
to be more specific about which repository to handle. This is a small
mechanical change; it doesn't change the implementation to handle
repositories other than the_repository yet.

As with the previous commits, use a macro to catch callers passing a
repository other than the_repository at compile time.

Signed-off-by: Stefan Beller <sbeller@google.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

pack-bitmap-write.c

@@ -73,7 +73,8 @@ void bitmap_writer_build_type_index(struct pack_idx_entry **index,
 			break;
 
 		default:
-			real_type = oid_object_info(&entry->idx.oid, NULL);
+			real_type = oid_object_info(the_repository,
+						    &entry->idx.oid, NULL);
 			break;
 		}