Comment 2 for bug 1967000

Reviewed: https://reviews.mahara.org/c/mahara/+/12690
Committed: https://git.mahara.org/mahara/mahara/commit/ef1c8a7c5579d27dc852cc9c65b3e0819fe9c48a
Submitter: "Robert Lyon <email address hidden>"
Branch: 21.04_DEV

commit ef1c8a7c5579d27dc852cc9c65b3e0819fe9c48a
Author: Fergus Whyte <email address hidden>
Date: Wed Mar 30 09:37:12 2022 +1300

Bug 1967000: Make skin use the processed viewskin value provided by object, rather than pull the value out of the database directly.

This fixes issues where new defaults have not been added to skins yet.

Also some security checking around the viewskin serialized data to
make sore there is no object structure hiding in it that could cause
code execution

And fixing an issue if we pass an empty string rather than a hex
to fetch the rgb value - can happen on import

Change-Id: I6cb81bf9fa77d259d305cefecca1aa11e1a3b629
(cherry picked from commit d409628b7f72e224b865823d5254f511bd67d070)