title: Default Request Header does not accept any value its always null
body: <p>I am doing an web api integration test.</p>
  
  <p>I want to pass my bearer token to the header of a Http Request:</p>
  
  <pre><code>httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", "eJ43k5l435j34l5j43l5j34l5jl35j34l5j344l.4534535.534534sample...");
  </code></pre>
  
  <p>When this line of code is done I look into the <code>httpClient.DefaultRequestHeaders.Authorization</code> property and it is NULL ?</p>
  
  <p>Why this?</p>
  
  <p><strong>UPDATE</strong></p>
  
  <p>This is from the base class of my integration test class:</p>
  
  <pre><code> protected HttpClient Client { get { return server.HttpClient; } }
  </code></pre>
  
  <p>When I manually new up a http client in the test class:</p>
  
  <pre><code>var client = new HttpClient();
  client.DefaultRequestHeaders.Add("key","value");
  </code></pre>
  
  <p>it works but not with my Client !?</p>
  
  <p><strong>UPDATE 2</strong></p>
  
  <p>OK I found this out:</p>
  
  <pre><code> var c = Client;
   c.DefaultRequestHeaders.Add("bla", "bla");
  </code></pre>
  
  <p>IT WORKS, but why do I have to read my client in a new variable?</p>