🐞 Bug report

Command (mark with an x)

- [ ] new
- [x] build
- [ ] serve
- [ ] test
- [ ] e2e
- [ ] generate
- [ ] add
- [ ] update
- [ ] lint
- [ ] xi18n
- [ ] run
- [ ] config
- [ ] help
- [ ] version
- [ ] doc

Is this a regression?

No.

Description

Zone.js does not support native async/await (angular/zone.js#1140) as present in ES2017. This means code that happens inside async/await blocks is invisible to zone.js thus not triggering change detection.

Since this is a footgun for developer, Angular CLI should show a warning about this when ES2017 is set as the typescript target.

🔬 Minimal Reproduction

angular/zone.js#1140

🔥 Exception or Error

No error, just no change detection.

🌍 Your Environment

Angular CLI 7.x

Anything else relevant?