title: How to silence "The feature name "router" does not exist in the state..." ngrx/router-store warning
body: <p>When I add "@ngrx/router-store" to my project, it spams the app console in development mode and unit test results with the following message:</p>
  
  <blockquote>
    <p>The feature name "router" does not exist in the state, therefore createFeatureSelector cannot access it.  Be sure it is imported in a loaded module using StoreModule.forRoot('router', ...) or StoreModule.forFeature('router', ...).  If the default state is intended to be undefined, as is the case with router state, this development-only warning message can be ignored.</p>
  </blockquote>
  
  <p>I tried to set <code>router</code> state property type to</p>
  
  <pre><code>router: null |  RouterReducerState&lt;SerializedRouterStateSnapshot&gt;
  </code></pre>
  
  <p>and initial state value to</p>
  
  <pre><code>router: null
  </code></pre>
  
  <p>but it clashes with <code>routerReducer</code> type, which only accepts </p>
  
  <pre><code>RouterReducerState&lt;SerializedRouterStateSnapshot&gt;
  </code></pre>
  
  <p>How do I disable this warning? I honestly find it rather annoying.</p>