The default import is replaced with only polyfills that are Stage 4; this is in alignment with how we have removed the Stage presets. This also would mean we would need to add new imports when necessary, but that can be in a future release.
PR #8418 introduced some new logic that uses the third parameter of `fs-readdir-recursive`'s `filter` option, the current directory, but missed that our dependencies only required `^1.0.0`, while that parameter was actually added in `1.1.0`. This means that if some other dependency forced a downgrade in the version to satisfy some range, or the user already had 1.0.0 module installed locally, it could cause problems,
In Babel 6, we had `@babel/runtime` which _always_ uses `core-js` in its helpers, meaning that anyone who wants to use our helpers in a centralized modular way had to also use core-js, which isn't always ideal.
Early in the Babel 7 alpha, we added a `useBuiltins: true` option that would use separate copies of the helpers that would skip loading `core-js`, but this _still_ requires users to have an indirect npm dependency on `core-js`.
This PR splits our setup into two separate runtimes:
* ```
'plugins': [
['transform-runtime'],
]
```
with `npm install --save @babel/runtime` that just includes our helpers, and relies on users to globally polyfill any APIs they need.
* ```
'plugins': [
['transform-runtime', { corejs: 2 }],
]
```
with `npm install --save @babel/runtime-corejs2` that includes everything `@babel/runtime` does, but also includes a passthrough API for `corejs@2.x` and rewrites all of the helper modules to reference `core-js`.
* Fix private property parsing in Flow
* Flow tests updated
* Fix type error
* Appropriate name was given to test folder
* Fix
* Empty
* Correct type annotation
* Add required changes in generator package
* Add required changes in flow-strip-types
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| Q | A <!--(Can use an emoji 👍) -->
| ------------------------ | ---
| Fixed Issues? | Fixes#7118
| Patch: Bug Fix? | Y
| Major: Breaking Change? | N
| Minor: New Feature? | N
| Tests Added + Pass? | Yes
| Documentation PR Link |
| Any Dependency Changes? |
| License | MIT
