code: function() {
      if(!this.isBase) {
        var self = this;
        var idx = this._searchLayerIndex();
        if(idx >= 0) {
          this.gmapsMap.overlayMapTypes.removeAt(idx);
        } else if (this.gmapsLayer.setMap){
          this.gmapsLayer.setMap(null);
        }
        this.model.unbind(null, null, this);
        this.unbind();
      }
    }
docs: remove layer from the map and unbind events