findPolicy() in modMediaSource always looks at the mgr context

[CarlBohman]

Bug report

Summary

The findPolicy function in core/model/modx/sources/modmediasource.class.php explicitly sets the $context to $mgr in all cases, ignoring any value sent into the function.

Step to reproduce

Look at the source code: https://github.com/modxcms/revolution/blob/3.x/core/src/Revolution/Sources/modMediaSource.php (line 1622 as of 6/22/2022). Here is a copy of the relevant code:

    public function findPolicy($context = '')
    {
        $policy = [];
        $enabled = true;
        $context = 'mgr';

Observed behavior

In one specific case on a site with access_resource_group_enabled turned off and log level set to info, this created a large number of errors related to the mgr context when trying to access pages in the web context. Deleting this line eliminated the errors and no side effects have been observed.

Expected behavior

No extraneous error messages and no attempts to look at the mgr context when accessing pages in the web context.

Environment

MODX version 2.8.3, but present in the current 3.x version of the code as well.

[CarlBohman]

Example of an error message that is generated:

[2022-05-11 20:00:03] (INFO @ /var/www/core/model/modx/modaccessibleobject.class.php : 40) Principal 0 does not have permission to load object of class modContext with primary key: mgr

This was traced back to the line setting the context explicitly to mgr.