Adds a feature flag for when React.jsx warns you about spreading a key into jsx. It's false for all builds, except as a dynamic flag for fb/www.
I also included the component name in the warning.
* Split recent passive effects changes into 2 flags
Separate flags can now be used to opt passive effects into:
1) Deferring destroy functions on unmount to subsequent passive effects flush
2) Running all destroy functions (for all fibers) before create functions
This allows us to test the less risky feature (2) separately from the more risky one.
* deferPassiveEffectCleanupDuringUnmount is ignored unless runAllPassiveEffectDestroysBeforeCreates is true
* Build both stable and experimental WWW builds
* Flip already experimental WWW flags to true
* Remove FB-specific internals from modern FB builds
We think we're not going to need these.
* Disable classic features in modern WWW builds
* Disable legacy ReactDOM API for modern WWW build
* Don’t include user timing in prod
* Fix bad copy paste and add missing flags to test renderer
* Add testing WWW feature flag file
We need it because WWW has a different meaning of experimental now.
This PR introduces adds `react/testing` and `react-dom/testing`.
- changes infra to generate these builds
- exports act on ReactDOM in these testing builds
- uses the new test builds in fixtures/dom
In the next PR -
- I'll use the new builds for all our own tests
- I'll replace usages of TestUtils.act with ReactDOM.act.