gplugin/gplugin

Make GPluginManager a final type

2021-10-12, Gary Kramlich
a1b0fd07c7f1
Make GPluginManager a final type

* Use g_signal_new_class_handler to handle the accumulator based signals
* Remove the optional struct offset for the non accumulator based signals
* This all fixes the warnings from vapigen as well

Testing Done:
Ran the unit tests, gplugin-query, and gplugin-gtk3-viewer without issue.

Reviewed at https://reviews.imfreedom.org/r/1028/
// SPDX-FileCopyrightText: 2021 GNOME Foundation
// SPDX-License-Identifier: LGPL-2.1-or-later
// A map between namespaces and base URLs for their online documentation
baseURLs = [
[ 'GLib', 'https://docs.gtk.org/glib/' ],
[ 'GObject', 'https://docs.gtk.org/gobject/' ],
[ 'GPlugin', 'https://docs.imfreedom.org/gplugin/' ],
[ 'GModule', 'https://docs.gtk.org/gmodule/' ],
[ 'Gtk3', 'https://docs.gtk.org/gtk3/' ],
]