Remove invalid option from style select
Remove invalid option from style select

When this option was selected the text field contained 'undefined'
as it is not one of the predefined styles.

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