We're switching Atom to React, but we want to support backward-compatible shims to our previous view framework.

In the old framework, views were represented as jQuery-wrapped DOM elements. Ideally, we'd like to provide backward-compatible shims by simply rendering the React component and wrapping its root element in a jQuery wrapper with an API that's compatible to our old editor views. That would essentially look like this:

``` javascript
var editorRoot = document.createElement('div')
React.renderComponentWithRootElement(Editor(props), editorRoot)

// the element would actually be wrapped in a custom subclass of jQuery,
// but this is clearer for this example
var editorShim = $(editorRoot) 
```

Currently, this isn't possible because React components need to be rendered into a container. So instead we need to create a wrapper element and render the component inside it. This is sad because it adds an extra layer of markup which confuses styling, and also means that the editor has a wrapper when used via the shim layer but no wrapper when embedded as a child via React itself.

Is there something fundamental preventing React from adopting DOM nodes directly without the parent? Is this something we could even hack in in a way that would be somewhat maintainable?

:heart:

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        value: 0,
      };
      static getDerivedStateFromProps(nextProps, prevState) {
        return {
          value: prevState.value + 1,
        };
      }
      getSnapshotBeforeUpdate(prevProps, prevState) {
        log.push(
          `getSnapshotBeforeUpdate() prevProps:${prevProps.value} prevState:${
            prevState.value
          }`,
        );
        return 'abc';
      }
      componentDidUpdate(prevProps, prevState, snapshot) {