ListView: Fix NRE when accessing the Theme property
ListView: Fix NRE when accessing the Theme property

The StyleSet signal in GTK 2 was fired when the widget was first
created. This is not the case with the new StyleUpdated signal in GTK 3.
So we need to call OnStyleUpdated in the ListView constructor, to make
sure things are properly initialized.

Signed-off-by: Bertrand Lorentz <eb7ac131ef7bff6d2ebccd6e5bf9a7cb6485cf2c@gmail.com>

arfbtwn/hyena,arfbtwn/hyena,GNOME/hyena,GNOME/hyena