allow client icon change events in ibar client prop handler
allow client icon change events in ibar client prop handler

fix T2284

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