code: function saveChildNodes$1(node) {
      if (!this.hasChildNodes(node)) {
        node.__dom = node.__dom || {};
        node.__dom.firstChild = node.firstChild;
        node.__dom.lastChild = node.lastChild;
        var c$ = node.__dom.childNodes = tree.arrayCopyChildNodes(node);
        for (var i=0, n; (i<c$.length) && (n=c$[i]); i++) {
          n.__dom = n.__dom || {};
          n.__dom.parentNode = node;
          n.__dom.nextSibling = c$[i+1] || null;
          n.__dom.previousSibling = c$[i-1] || null;
          common.patchNode(n);
        }
      }
    }
docs: Capture the list of light children. It's important to do this before we start transforming the DOM into "rendered" state. Children may be added to this list dynamically. It will be treated as the source of truth for the light children of the element. This element's actual children will be treated as the rendered state once this function has been called.