Only variables should be passed by reference in - php

Question

I inherited maintenance of a Drupal 7 website and I have zero PHP experience and I need some help. I have just updated Drupal to 7.31 and am getting the error "Only variables should be passed by reference in..." on lines 43 and 86 of an .inc file.
Here is line 43:
$item = array_shift(array_values($data));
Here is line 86:
$item = array_shift(array_values($data));
Can anyone help me out?
I don't know if this is allowed but here the code for the .inc file
<?php
$plugin = _cdd_core_content_type_plugin('nauticus_core', 'menu_full_leaf', 'Page: menu leaf', array(
'description' => 'Add menu children',
), array(
'override_title' => 1,
'override_title_text' => ''
), 'Sail Nauticus');
function nauticus_core_menu_full_leaf_content_type_plugin_render($subtype, &$conf, $panel_args) {
$trail = menu_get_active_trail();
$menu = '';
if (is_array($trail)) {
$leaf = array_pop($trail);
if (isset($leaf['menu_name'])) {
$menu_name = $leaf['menu_name'];
if ($menu_name !== 'navigation') {
$depth = $leaf['depth'];
$p1 = $leaf['p1'];
$data = menu_tree_page_data($menu_name, $depth + 1);
foreach ($data as $i => $item) {
if ($item['link']['mlid'] !== $leaf['plid']
&& !($leaf['plid'] == 0 && ($item['link']['mlid'] == $leaf['mlid']))
) {
unset($data[$i]);
}
}
if (sizeof($data) > 1) {
$menu = menu_tree_output($data);
foreach ($menu as $i => $item) {
if (isset($item['#original_link'])) {
if ($item['#original_link']['mlid'] !== $p1) {
if (isset($menu[$i]['#below'])) {
$menu[$i]['#below'] = array();
}
}
}
}
}
elseif (sizeof($data) == 1) {
$item = array_shift(array_values($data));
if (isset($item['below']) && !empty($item['below'])) {
$menu = menu_tree_output($item['below']);
foreach ($menu as $i => $item) {
if (isset($item['#original_link'])) {
if ($item['#original_link']['mlid'] !== $p1) {
if (isset($menu[$i]['#below'])) {
$menu[$i]['#below'] = array();
}
}
}
}
}
}
}
}
}
return $menu;
}
function nauticus_core_menu_full_leaf_content_type_plugin_title($subtype, &$conf, $panel_args) {
$title = 'Navigation';
$trail = menu_get_active_trail();
if (is_array($trail)) {
$leaf = array_pop($trail);
if (isset($leaf['menu_name'])) {
$menu_name = $leaf['menu_name'];
if ($menu_name !== 'navigation') {
$depth = $leaf['depth'];
$p1 = $leaf['p1'];
$data = menu_tree_page_data($menu_name, $depth + 1);
foreach ($data as $i => $item) {
if ($item['link']['mlid'] !== $leaf['plid']
&& !($leaf['plid'] == 0 && ($item['link']['mlid'] == $leaf['mlid']))
) {
unset($data[$i]);
}
}
if (sizeof($data) >= 1) {
$item = array_shift(array_values($data));
if (isset($item['link']) && !empty($item['link'])) {
if (isset($item['link']['link_title'])) {
$title = $item['link']['link_title'];
}
}
}
}
}
}
return $title;
}

Answer 1

array_shift requires that the first argument be a pass by reference and array_values returns an array.
change those lines that you have $item = array_shift(array_values($data)); to
$item = array_values($data);
$item = array_shift(&$item);
the & means the variable is pass by reference. This should fix your problem.
if that does not work just remove the &.

Answer 2

Change
$item = array_shift(array_values($data));
to
$tmp = array_values($data);
$item = array_shift($tmp);