RxJs ships generators instead of native async/await

[JeanMeche]

Describe the bug

Talking about v7:

Looking at files like /rxjs/dist/esm/internal/observable/innerFrom.js, it looks like rxjs is shipping code where native async/awaits are converted to generators.

I don't think that's up to the lib to do that conversion.

Soon, zoneless Angular apps should be able to build without using @babel/plugin-transform-async-to-generator (required by zone.js. So I would expect rxjs to ship native async/await and reduce its footprint.

Version

7.8.1

[kwonoj]

#5270

We won't make breaking changes to the target platform we support in v7. If we change transpilation target, consumer need to separately transpile 3rd party pkg (rxjs).