Couple of small fixes to event system.
Couple of small fixes to event system.

hronoses/vispy,jay3sh/vispy,julienr/vispy,sbtlaarzc/vispy,RebeccaWPerry/vispy,sh4wn/vispy,michaelaye/vispy,sh4wn/vispy,hronoses/vispy,michaelaye/vispy,kkuunnddaannkk/vispy,hronoses/vispy,jay3sh/vispy,Eric89GXL/vispy,drufat/vispy,QuLogic/vispy,kkuunnddaannkk/vispy,jdreaver/vispy,Eric89GXL/vispy,drufat/vispy,RebeccaWPerry/vispy,ghisvail/vispy,dchilds7/Deysha-Star-Formation,jay3sh/vispy,sh4wn/vispy,bollu/vispy,dchilds7/Deysha-Star-Formation,julienr/vispy,sbtlaarzc/vispy,ghisvail/vispy,inclement/vispy,bollu/vispy,srinathv/vispy,dchilds7/Deysha-Star-Formation,QuLogic/vispy,QuLogic/vispy,inclement/vispy,ghisvail/vispy,sbtlaarzc/vispy,jdreaver/vispy,drufat/vispy,srinathv/vispy,michaelaye/vispy,kkuunnddaannkk/vispy,Eric89GXL/vispy,jdreaver/vispy,RebeccaWPerry/vispy,julienr/vispy,srinathv/vispy,bollu/vispy,inclement/vispy