alize the drawing manager.
        var drawingManager = new google.maps.drawing.DrawingManager({
          drawingMode: google.maps.drawing.OverlayType.POLYGON,
          drawingControl: true,
          drawingControlOptions: {
            position: google.maps.ControlPosition.TOP_LEFT,
            drawingModes: [
              google.maps.drawing.OverlayType.POLYGON
            ]
          }
        });

        // Style the markers a bit. This will be our listing marker icon.
        var defaultIcon = mak