shell: Scale fullscreen surface without cropping them, center on output
shell: Scale fullscreen surface without cropping them, center on output

Fantu/compositor-spice,udoprog/weston,sir-murray/weston,eyolfson/weston,udoprog/weston,xorgy/weston,mchalupa/weston,xorgy/weston,giucam/weston,Fantu/compositor-spice,eyolfson/weston,jonnylamb/weston,sir-murray/weston,jonnylamb/weston,kwm81/weston,Fantu/compositor-spice,giucam/weston,mchalupa/weston,kwm81/weston,Tarnyko/weston-xdg_surface_present,Tarnyko/weston-xdg_surface_present,krezovic/weston,krezovic/weston,Gnurou/weston,Gnurou/weston