message: docs: add changelog for 5.0.0-beta.4
diff: +<a name="5.0.0-beta.4"></a>
  +# [5.0.0-beta.4](https://github.com/angular/angular/compare/5.0.0-beta.3...5.0.0-beta.4) (2017-08-16)
  +
  +
  +### Bug Fixes
  +
  +* **aio:** fix compilation error by using the correct type for `providers` ([4d523fd](https://github.com/angular/angular/commit/4d523fd))
  +* **aio:** skip PWA test when redeploying non-public commit ([06faac8](https://github.com/angular/angular/commit/06faac8))
  +* **compiler:** Don't strip CSS source maps ([64b4be9](https://github.com/angular/angular/commit/64b4be9))
  +* **forms:** re-assigning options should not clear select ([32ff21c](https://github.com/angular/angular/commit/32ff21c)), closes [#18330](https://github.com/angular/angular/issues/18330)
  +* **language-service:** remove tsickle dependency ([bc22ff1](https://github.com/angular/angular/commit/bc22ff1))
  +
  +
  +### Features
  +
  +* **common:** mark NgTemplateOutlet API as stable ([0a73e8d](https://github.com/angular/angular/commit/0a73e8d))
  +* **forms:** add status to `AbstractControlDirective` ([233ef93](https://github.com/angular/angular/commit/233ef93))
  +* **forms:** add updateOn support to ngModelOptions ([1cfa79c](https://github.com/angular/angular/commit/1cfa79c))
  +
  +
  +### Performance Improvements
  +
  +* **aio:** update to new version of build-optimizer ([088532b](https://github.com/angular/angular/commit/088532b))
  +* **core:** add option to remove blank text nodes from compiled templates ([d2c0d98](https://github.com/angular/angular/commit/d2c0d98))
  +* **core:** Remove decorator DSL which depends on Reflect ([cac130e](https://github.com/angular/angular/commit/cac130e))
  +
  +
  +
  <a name="4.3.5"></a>
  ## [4.3.5](https://github.com/angular/angular/compare/4.3.4...4.3.5) (2017-08-16)
  