slightly optimize shape cutting
slightly optimize shape cutting

objects below the bottom client are unnecessary, so it's better to just start with the bottom client. this has a nice side effect of working around a weird evas bug where layers can exist while having no objects, breaking stacking iterator functions

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