ui: listen for GDK_SMOOTH_SCROLL events

On Wayland, without grabbing focus, two-finger scrolling generates
GDK_SMOOTH_SCROLL events instead of GDK_SCROLL_*, so listen for them.

Signed-off-by: Sergio Lopez <slp@redhat.com>
Message-id: 20190204120823.41333-1-slp@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
1 file changed