clear x11 client pixmap when returning from iconic
clear x11 client pixmap when returning from iconic

ensure pixmap remains usable during the entire hide process

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