gobject: Allow install_properties with 1 GParamSpec
g_object_install_properties()
can be used to install multiple
properties at once, and to allow an optimization for property
notification. Arguably, using it over g_object_install_property()
is
best practice. That being said, you can't use it if you have only a
single property that is installed (yet), due to a precondition check for
more than 1 pspecs.