[view/map,bugfix][xs]: be more cautious about assuming a location field actually gains geodata (and geojson specifically).

* At present giving data with e.g. { location: 'New York'} would lead the view to crash on a JSON parsing error.

src/view-map.js

@@ -345,8 +345,11 @@ my.Map = Backbone.View.extend({
       if (this.state.get('geomField')){
         var value = doc.get(this.state.get('geomField'));
         if (typeof(value) === 'string'){
-          // We have a GeoJSON string representation
+          // We *may* have a GeoJSON string representation
-          return $.parseJSON(value);
+          try {
+            return $.parseJSON(value);
+          } catch(e) {
+          }
         } else {
           // We assume that the contents of the field are a valid GeoJSON object
           return value;