ENYO-923: Listen focus, blur window events only when webos version > 4
ENYO-923: Listen focus, blur window events only when webos version > 4

Add conditional events listening.

DCO-1.1-Signed-Off-By: Kunmyon Choi kunmyon.choi@lge.com

PKRoma/enyo,mcanthony/enyo,kustomzone/enyo,bright-sparks/enyo,mcanthony/enyo,wikieswan/enyo,kustomzone/enyo,enyojs/enyo,bright-sparks/enyo,beni55/enyo,enyojs/enyo,soapdog/enyo,soapdog/enyo,PKRoma/enyo,wikieswan/enyo,beni55/enyo