THIS_DOC);
      Polymer.dom(this).appendChild(node);

      const info = Polymer.dom(this).querySelector('.image-info');
      this.sizeInfo_ = Polymer.dom(info).querySelector('.size');

      this.imageContainer_ =
          Polymer.dom(this).querySelector('.image-container');
      this.image_ = Polymer.dom(this.imageContainer_).querySelector('img');

      this.zoomScaleValue_ = 1;
      this.trackMouse_();
    },

    updateContents() {
      if (this.objectSnapshot_ &&
          this.objectSnapshot_.d