gplugin/gplugin

Simplify some error freeing

13 months ago, Elliott Sales de Andrade
574a15115c40
Simplify some error freeing

Also, clarify the state of an `error` in a test.

Testing Done:
Compiled and ran tests.

Reviewed at https://reviews.imfreedom.org/r/2380/
EionRobb <> EionRobb <eion@robbmob.com>
ivanhoe <107501-ivanhoe@users.noreply.gitlab.com> ivanhoe <ivanhoe@fiscari.de>
Richard Laager <rlaager@pidgin.im> <rlaager@wiktel.com>