Finally on Nov 19 2013, Google shut down Google Maps v2 API, which was depreciated in May 19 2010 but was working continuously Nov 19. I was aware of version depreciation, but I procrastinate to upgrade till last minute because of working on too many other things. While checking my Web map (built on Openlayers, Geoserver and Google Maps as base layers (Google Maps API v2) on Nov 20, I saw two map controls one from Openlayers and other from Google Maps API also noticed that map application was unresponsive.
Looking around I found easy steps to fix it without major change in the code-