Catch error in case $destroy is called twice

This error can happen when using ui-router, as ui-router will manage
your application lifecycle incorrectly. See this issue for more
information:

angular-ui/ui-router#881

Author: Wylie Conlon

dist/angular-leaflet-directive.js

@@ -138,8 +138,11 @@ angular.module("leaflet-directive", []).directive('leaflet', ["$q", "leafletData
             });
 
             scope.$on('$destroy', function () {
-                map.remove();
-                leafletData.unresolveMap(attrs.id);
+                try {
+                    map.remove();
+                    leafletData.unresolveMap(attrs.id);
+                } catch (e) {
+                }
             });
 
             //Handle request to invalidate the map size