tree: use repo_parse_tree()

e092073 (tree.c: make read_tree*() take 'struct repository *',
2018-11-18) replaced explicit uses of the_repository.  parse_tree() uses
it internally, though, so call repo_parse_tree() instead and hand it the
correct repository.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: rscharfe

tree.c

@@ -28,7 +28,7 @@ int read_tree_at(struct repository *r,
 	if (depth > r->settings.max_allowed_tree_depth)
 		return error("exceeded maximum allowed tree depth");
 
-	if (parse_tree(tree))
+	if (repo_parse_tree(r, tree))
 		return -1;
 
 	init_tree_desc(&desc, &tree->object.oid, tree->buffer, tree->size);