The g_value_register_transform_func() for handling GBytes was not actually used.
All properties of type G_TYPE_BYTES have their explit handler how to convert bytes
to string. That is good, because the implementation there was very bad (it did not
honor pretty/parsable get-type).
Also, merge _get_fcn_gobject_bytes() into _get_fcn_gobject_impl(). We
already have a generic handler that handles properties solely based on
the GObject type: _get_fcn_gobject_impl(). Just let it also handle
bytes. It's better to have fewer handlers, if they don't need special
context.
e55a45faa2