stopDrawingMode() {
    if (this._isSameDrawingMode(drawingModes.NORMAL)) {
      return;
    }

    const drawingModeInstance = this._getDrawingModeInstance(this.getDrawingMode());
    if (drawingModeInstance && drawingModeInstance.end) {
      drawingModeInstance.end(this);
    }
    this._drawingMode = drawingModes.NORMAL;
  }
Stop the current drawing mode and back to the 'NORMAL' mode