Update external-map.js
Update external-map.js

Handle situations when main window loose focus - e.g. by selecting of differen browser tab.

bjornharrtell/ol3,oterral/ol3,stweil/openlayers,ahocevar/openlayers,bjornharrtell/ol3,stweil/openlayers,ahocevar/ol3,oterral/ol3,stweil/openlayers,bjornharrtell/ol3,ahocevar/ol3,oterral/ol3,openlayers/openlayers,ahocevar/openlayers,ahocevar/ol3,openlayers/openlayers,ahocevar/openlayers,ahocevar/ol3,openlayers/openlayers