title: Blazor does not refresh UI when parameter is passed with onclick function
body: <p>In Blazor ServerSide Asp.net core 3.0 Preview 6 the UI does not refresh. 
  I have altered the counter.razor as an example. 
  If you click the buttons "Set counter to ..." the counter is not refreshed. When you click the "Click me" button (is without a parameter) the UI is refreshed and 1 is added to the counter previous clicked.</p>
  
  <p>The buttons seems to work, but the UI is not refreshed.</p>
  
  <pre><code>@page "/counter"
  
  &lt;h1&gt;Counter&lt;/h1&gt;
  
  &lt;p&gt;Current count: @currentCount&lt;/p&gt;
  &lt;br /&gt;
  
  &lt;p&gt;
      &lt;button class="btn btn-primary" @onclick="@IncrementCount"&gt;Click me&lt;/button&gt;
  &lt;/p&gt;
  
      @for (int i = 0; i &lt; 5; i++)
      {
          var a = i;
          &lt;p&gt;&lt;button class="btn btn-primary" onclick="@(() =&gt; test(a))"&gt;Set counter to @a&lt;/button&gt;&lt;/p&gt;
      }
  
      @functions {
          int currentCount = 0;
  
          protected void IncrementCount()
          {
              currentCount++;
          }
  
          void test(int i)
          {
              currentCount = i;
          }
      }
  </code></pre>
  
  <p>Any suggestions how to fix this is or is it a bug in Blazor?</p>