 
   let spacing = CGFloat(1)
   let inset = CGFloat(16)
-  let headerMinHeight = CGFloat(48)
   let node: CBCNode
   var headerViewController: MDCFlexibleHeaderViewController
   var titleLabel: UILabel

#if swift(>=3.2)
  @available(iOS 11, *)
  override func viewSafeAreaInsetsDidChange() {
    self.headerViewController.headerView.minimumHeight =
        headerMinHeight + self.view.safeAreaInsets.top

    // Re-constraint the title label to account for changes in safeAreaInsets's left and right.
    let titleInsets = UIEdgeInsets(top: 0,
                                   left: inset + self.view.safeAreaInsets.left,


    self.addChildViewController(self.headerViewController)

    self.headerViewController.headerView.minMaxHeightIncludesSafeArea = false
    self.headerViewController.headerView.maximumHeight = 108

    self.collectionView?.register(MDCCatalogCollectionViewCell.self,
      forCellWithReuseIdentifier: "MDCCatalogCollectionViewCell")
