- ts-api-guardian will now error if a new public symbol is added with a stability marker (`@stable`, `@experimental`, `@deprecated`)
- DomEventsPlugin and KeyEventsPlugin were removed from public api surface - these classes is an implementation detail
- deprecated BROWSER_PROVIDERS was removed completely
- `@angular/compiler` was removed from the ts-api-guardian check since this package shouldn't contain anything that users need to directly import
- the rest of the api surface was conservatively marked as stable or experimental
BREAKING CHANGES: DomEventsPlugin and KeyEventsPlugin previously exported from core are no longer public - these classes are implementation detail.
Previously deprecated BROWSER_PROVIDERS was completely removed from platform-browser.
Closes#9236Closes#9235
Ref #9234
Mostly, removing things that were never intended to be exported publicy.
BREAKING CHANGE:
The following are no longer publicly exported APIs. They were intended as internal
utilities and you should use your own util:
```
browserDetection,
dispatchEvent,
el,
normalizeCSS,
stringifyElement,
expect (and custom matchers for Jasmine)
```