read-cache.c: remove the_* from index_has_changes()

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/read-cache.c b/read-cache.c
index 61cc057..2549477 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -2365,22 +2365,20 @@ int unmerged_index(const struct index_state *istate)
 	return 0;
 }
 
-int index_has_changes(struct index_state *istate,
-		      struct tree *tree,
-		      struct strbuf *sb)
+int repo_index_has_changes(struct repository *repo,
+			   struct tree *tree,
+			   struct strbuf *sb)
 {
+	struct index_state *istate = repo->index;
 	struct object_id cmp;
 	int i;
 
-	if (istate != &the_index) {
-		BUG("index_has_changes cannot yet accept istate != &the_index; do_diff_cache needs updating first.");
-	}
 	if (tree)
 		cmp = tree->object.oid;
 	if (tree || !get_oid_tree("HEAD", &cmp)) {
 		struct diff_options opt;
 
-		repo_diff_setup(the_repository, &opt);
+		repo_diff_setup(repo, &opt);
 		opt.flags.exit_with_status = 1;
 		if (!sb)
 			opt.flags.quick = 1;