Repository: angular
Issue: writeValue gets called before ngOnInit
Labels: type: bug/fix,freq2: medium,area: forms,state: confirmed,P4

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# 🐞 bug report

### Affected Package
<!-- Can you pin-point one or more @angular/* packages as the source of the bug? -->
<!-- ✍️edit: --> The issue is caused by package `@angular/forms`


### Is this a regression?

<!-- Did this behavior use to work in the previous version? -->
<!-- ✍️-->
I don't know. I don't think so.


### Description

<!-- ✍️-->
When `NgControl` is injected into the constructor of a component and the value accessor is set manually to avoid `cyclic dependency errors`, `writeValue` is called before `ngOnInit`.
This workaround is suggested by the [Material Angular doc](https://material.angular.io/guide/creating-a-custom-form-field-control#-code-ngcontrol-code-) under `ngControl`.


## 🔬 Minimal Reproduction
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[Stackblitz](https://stackblitz.com/edit/angular-form-control-bug)

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## 🌍  Your Environment

**Angular Version:**
<pre><code>
Angular CLI: 7.3.5
Node: 11.9.0
OS: win32 x64
Angular: 7.2.8
... animations, common, compiler, compiler-cli, core, forms
... http, language-service, platform-browser
... platform-browser-dynamic, router, service-worker

Package                           Version
-----------------------------------------------------------
@angular-devkit/architect         0.13.5
@angular-devkit/build-angular     0.13.5
@angular-devkit/build-optimizer   0.13.5
@angular-devkit/build-webpack     0.13.5
@angular-devkit/core              7.3.5
@angular-devkit/schematics        7.3.5
@angular/cdk                      7.3.3
@angular/cli                      7.3.5
@angular/material                 7.3.3
@angular/pwa                      0.13.5
@ngtools/webpack                  7.3.5
@schematics/angular               7.3.5
@schematics/update                0.13.5
rxjs                              6.4.0
typescript                        3.2.4
webpack                           4.29.0
</code></pre>

**Anything else relevant?**
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 I was sent here by the @angular/material2 team. They believe it's an issue with `@angular/forms`.
[https://github.com/angular/material2/issues/15434](https://github.com/angular/material2/issues/15434)