make client util functions take NULL more gracefully
make client util functions take NULL more gracefully

tasn/enlightenment,tizenorg/platform.upstream.enlightenment,rvandegrift/e,rvandegrift/e,tasn/enlightenment,FlorentRevest/Enlightenment,FlorentRevest/Enlightenment,rvandegrift/e,tasn/enlightenment,tizenorg/platform.upstream.enlightenment,FlorentRevest/Enlightenment,tizenorg/platform.upstream.enlightenment