TreeView: PHP 7.3 issue in AJAXTree

[AiYoriAoshi]

There is a problem with the TreeView with PHP 7.3. I haven't tested any other PHP Version but from the mailing list it seems that PHP 7.2 works fine.

The problem is in the AJAXTree.php file from PLA.
The tree will show the "alt" +- Text instead of an expand/collapse icon as the code for the icons does not work and since the code relies on the displayed icon name to decide on further action, no action will be carried out since no icon was loaded.

>/usr/share/ldap-account-manager/templates/3rdParty/pla/lib#` diff AJAXTree.php.old AJAXTree.php
> 68,69c65,66
<               $imgs['expand'] = array('tree_expand.png','tree_expand.png','tree_expand_corner.png',
<                       ($level > 0) ? 'tree_expand_corner.png' : 'tree_expand_corner_first.png');
---
>               $imgs['expand'] = array('tree_expand.png','tree_expand.png','tree_expand_corner.png');
>               $imgs['expand'][3] = ($level > 0) ? 'tree_expand_corner.png' : 'tree_expand_corner_first.png';
71,72c68,69
<               $imgs['collapse'] = array('tree_collapse.png','tree_collapse.png','tree_collapse_corner.png',
<                       ($level > 0) ? 'tree_collapse_corner.png' : 'tree_collapse_corner_first.png');
---
>               $imgs['collapse'] = array('tree_collapse.png','tree_collapse.png','tree_collapse_corner.png');
>               $imgs['collapse'][3] = ($level > 0) ? 'tree_collapse_corner.png' : tree_collapse_corner_first.png';

The issue is that code with inline-conditioning the $level variable results not in an Array but returns UNKNOWN.
I'm no expert on PHP7, so my local quick fix was to just build the array with the three static entries and add the fourth value with the condition.

Now an array will be successfully build and the tree can be expanded/collapsed.

[gruberroland]

Fixed with
716d119