code: function mountChildren(nestedChildren, transaction, context) {
        var children = this._reconcilerInstantiateChildren(nestedChildren, transaction, context);
        this._renderedChildren = children;
  
        var mountImages = [];
        var index = 0;
        for (var name in children) {
          if (children.hasOwnProperty(name)) {
            var child = children[name];
            var selfDebugID = 0;
            if (false) {
              selfDebugID = getDebugID(this);
            }
            var mountImage = ReactReconciler.mountComponent(child, transaction, this, this._hostContainerInfo, context, selfDebugID);
            child._mountIndex = index++;
            mountImages.push(mountImage);
          }
        }
  
        if (false) {
          setChildrenForInstrumentation.call(this, children);
        }
  
        return mountImages;
      }
docs: Generates a "mount image" for each of the supplied children. In the case
  of `ReactDOMComponent`, a mount image is a string of markup.
  
  @param {?object} nestedChildren Nested child maps.
  @return {array} An array of mounted representations.
  @internal