title: How to extend a component with dependency injection?
body: <p>I have the following class <code>ModuleWithHttp</code>:</p>
  
  <pre class="lang-js prettyprint-override"><code>@Injectable()
  export default class {
    constructor(private fetchApi: FetchApi) {}
  }
  </code></pre>
  
  <p>and I want to use it as follows:</p>
  
  <pre class="lang-js prettyprint-override"><code>@Component({
    selector: 'main',
    providers: [FetchApi]
  })
  export default class extends ModuleWithHttp {
    onInit() {
      this.fetchApi.call();
    }
  }
  </code></pre>
  
  <p>So by extending a super class that already injects a dependency I want to have an access to it in its children.</p>
  
  <p>I tried many different ways, even having super-class as a component:</p>
  
  <pre class="lang-js prettyprint-override"><code>@Component({
    providers: [FetchApi]
  })
  export default class {
    constructor(private fetchApi: FetchApi) {}
  }
  </code></pre>
  
  <p>But still, <code>this.fetchApi</code> is <code>null</code>, even in super-class.</p>