dillon1000/react

Fix AMD and Brunch issues (#8686)

* Add manual build fixtures

* Inject ReactDOM into ReactWithAddons from ReactWithAddons

We used to read ReactDOM as a global inside ReactAddonsDOMDependenciesUMDShim.
This didn't work in AMD environments such as RequireJS and SystemJS.

Instead, I changed it so that ReactDOM gets injected into ReactWithAddons by ReactDOM itself.
This way we don't have to try to require it (which wouldn't work because AMD doesn't handle circular dependencies well).

This means you have to load ReactDOM first before using ReactDOM-dependent addons, but this was already the case before.

This commit makes all build fixtures pass.

* Memoize ReactDOM to avoid going into require on every access

* Add Brunch fixture

* Inline requires to work around Brunch bug

See #8556 and https://github.com/brunch/brunch/issues/1591#issuecomment-270742503 for context.
This appears to be a Brunch bug but we can keep a temporary fix until the next major.