[email protected] and core-js@3 support?

[ztyzbb]

What problem does this feature solve?

For future
https://babeljs.io/blog/2019/03/19/7.4.0
https://github.com/zloirock/core-js/blob/master/docs/2019-03-19-core-js-3-babel-and-a-look-into-the-future.md

What does the proposed API look like?

plugins: [
  ["@babel/transform-runtime", {
    corejs: 3,
  }]
  ["@babel/preset-env", {
    useBuiltIns: "usage",
    corejs: 3,
  }]
]

[haoqunjiang]

Will be upgraded in v4, as addressed in the roadmap #3649