dillon1000/react

Refactor React.Children to reduce indirection (#18332)

* Don't pool traversal context

* Remove traverseAllChildrenImpl indirection

All usages are internal so we can simply use the inner function directly.

* Implement forEach through map

* Remove second usage of traverseAllChildren

This isn't useful by itself but makes the layering easier to follow. traverseAllChildren is only used at the lowest layer now.

* Reimplement count() and toArray() in terms of map()

* Inline the only use of mapSingleChildIntoContext

* Move forEach down in the file

* Use the language

Get rid of the traversal context. Use closures.

* Make mapIntoArray take an already escaped prefix

* Move count state out of mapIntoArray

* Inline traverseAllChildren into mapIntoArray

* Inline handleChild into mapIntoArray