[0.4.x] Plugin "gforce": severe warnings "no return statement in function returning non-void [-Wreturn-type]"

[hartwork]

I ran into this while packaging:

 * QA Notice: Package triggers severe warnings which indicate that it
 *            may exhibit random runtime failures.
 * /var/tmp/portage/media-plugins/libvisual-plugins-0.4.2/work/libvisual-plugins-0.4.2/plugins/actor/G-Force/Common/UI/ScreenDevice.cpp:462:1: warning: no return statement in function returning non-void [-Wreturn-type]
 * /var/tmp/portage/media-plugins/libvisual-plugins-0.4.2/work/libvisual-plugins-0.4.2/plugins/actor/G-Force/Common/UI/ScreenDevice.cpp:511:1: warning: no return statement in function returning non-void [-Wreturn-type]
 * /var/tmp/portage/media-plugins/libvisual-plugins-0.4.2/work/libvisual-plugins-0.4.2/plugins/actor/G-Force/Common/UI/EgOSUtils.cpp:346:1: warning: no return statement in function returning non-void [-Wreturn-type]
 * /var/tmp/portage/media-plugins/libvisual-plugins-0.4.2/work/libvisual-plugins-0.4.2/plugins/actor/G-Force/Common/UI/EgOSUtils.cpp:388:1: warning: no return statement in function returning non-void [-Wreturn-type]
 * /var/tmp/portage/media-plugins/libvisual-plugins-0.4.2/work/libvisual-plugins-0.4.2/plugins/actor/G-Force/Common/UI/ScreenDevice.cpp:462:1: warning: no return statement in function returning non-void [-Wreturn-type]
 * /var/tmp/portage/media-plugins/libvisual-plugins-0.4.2/work/libvisual-plugins-0.4.2/plugins/actor/G-Force/Common/UI/ScreenDevice.cpp:511:1: warning: no return statement in function returning non-void [-Wreturn-type]
 * /var/tmp/portage/media-plugins/libvisual-plugins-0.4.2/work/libvisual-plugins-0.4.2/plugins/actor/G-Force/Common/UI/EgOSUtils.cpp:346:1: warning: no return statement in function returning non-void [-Wreturn-type]
 * /var/tmp/portage/media-plugins/libvisual-plugins-0.4.2/work/libvisual-plugins-0.4.2/plugins/actor/G-Force/Common/UI/EgOSUtils.cpp:388:1: warning: no return statement in function returning non-void [-Wreturn-type]