Invalid argument supplied for foreach() in upload_save

After applying the patch committed here:
http://drupal.org/node/42358

When adding/editing a node with no uploads I get the "Invalid argument supplied for foreach()" error related to the following snippet:

function upload_save($node) {
  foreach ($node->files as $fid => $file) {
  ...

upload_save() is called from upload_nodeapi(), for op IN ('insert', 'update')

Not sure if this may happen somewhere else, it might be fixed checking if $node->files is an array:

function upload_save($node) {
  if (is_array($node->files) {
    foreach ($node->files as $fid => $file) {
    ...

I think the same problem may happen here:

function upload_delete_revision($node) {
  foreach ($node->files as $file) {

Also, I think there is a redundant check in _upload_validate(). The following:

function _upload_validate(&$node) {
  // Accumulator for disk space quotas.
  $filesize = 0;


  // Check if node->files exists, and if it contains something.
  if (count($node->files) && is_array($node->files)) {
    // Update existing files with form data.
    foreach($node->files as $fid => $file) {

could probably look like:

function _upload_validate(&$node) {
  // Accumulator for disk space quotas.
  $filesize = 0;


  // Check if node->files is an array.
  if (is_array($node->files)) {
    // Update existing files with form data.
    foreach($node->files as $fid => $file) {