code: function forEachChildren(children, forEachFunc, forEachContext) {
    if (children == null) {
      return children;
    }
    var traverseContext =
      ForEachBookKeeping.getPooled(forEachFunc, forEachContext);
    traverseAllChildren(children, forEachSingleChild, traverseContext);
    ForEachBookKeeping.release(traverseContext);
  }
docs: Iterates through children that are typically specified as `props.children`.
  
  The provided forEachFunc(child, index) will be called for each
  leaf child.
  
  @param {?*} children Children tree container.
  @param {function(*, int)} forEachFunc
  @param {*} forEachContext Context for forEachContext.