React Storybook shows `undefined` for composed components

[daneah]

Expected behavior

When a component is composed of other components, Storybook shows a tabbed interface for the resulting component and each of its constituent components.

Actual behavior

In the React Storybook, the resulting component shows as undefined, and for some components can't automatically generate the controls available.

Steps to reproduce the issue

1. Go to Storybook
2. Visit a composed component like RadioGroup or InputGroup in the React section
3. Observe the tab title and (for some components) the lack of controls