updateDurabilityLayout() {
    if (this._durabilitySprites != null && this._durabilitySprites.length > 0) {
      // show and position all durability sprites
      const contentSize = this.getContentSize();
      const durabilitySpriteContentSize = this._durabilitySprites[0].getContentSize();
      const durabilitySpriteHeight = durabilitySpriteContentSize.height - 8.0;
      const numDurabilitySprites = this._durabilitySprites.length;
      const { durabilityOnLeft } = this;
      const x = durabilityOnLeft ? 0.0 : contentSize.width;
      let y = (contentSize.height - (durabilitySpriteHeight * numDurabilitySprites)) * 0.5 + 8.0;
      for (let i = 0; i < numDurabilitySprites; i++) {
        const durabilitySprite = this._durabilitySprites[i];
        durabilitySprite.setPosition(x + (durabilityOnLeft ? -8.0 : 8.0), y);
        y += durabilitySpriteHeight;
      }
    }
  }
Updates the internal layout of durability sprites in this node.