title: cortana SetPhraseListAsync in uwp strange behavior
body: <p>I'm trying to update programmatically the phraselist in a UWP app, I followed the cortana uwp sample and this code doesn't work:</p>
  
  <pre><code>   VoiceCommandDefinition commandDefinitions;
  
                      if (VoiceCommandDefinitionManager.InstalledCommandDefinitions.TryGetValue("xxxCommandSet_en-us", out commandDefinitions))
                      {
  
                              System.Diagnostics.Debug.WriteLine("favouriteStringList not null ");
                              await commandDefinitions.SetPhraseListAsync("favourite", favouritesList);
  }
  </code></pre>
  
  <p>when I try with windows phone 8 approach it works</p>
  
  <pre><code>  Windows.Media.SpeechRecognition.VoiceCommandSet commandSetEnUs;
  
                  if (Windows.Media.SpeechRecognition.VoiceCommandManager.InstalledCommandSets.TryGetValue("xxxCommandSet_en-us", out commandSetEnUs))
                  {
                      await commandSetEnUs.SetPhraseListAsync(
                        "favourite", favouritesList);
                  }
  </code></pre>
  
  <p>here there is my VCD file</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8" ?&gt;
  &lt;VoiceCommands xmlns="http://schemas.microsoft.com/voicecommands/1.2"&gt;
    &lt;CommandSet xml:lang="en-us" Name="xxxCommandSet_en-us"&gt;
  
      &lt;AppName&gt; xxx &lt;/AppName&gt;
      &lt;Example&gt; Book a yyy in my favourite home &lt;/Example&gt;
  
      &lt;Command Name="bookyyyInFavourite"&gt;
        &lt;Example&gt; Book a yyy in my favourite home &lt;/Example&gt; &lt;!--Book xxx a yyy in my favourite home--&gt;
        &lt;ListenFor RequireAppName="BeforeOrAfterPhrase"&gt; book [me] a yyy in my favourite {favourite} &lt;/ListenFor&gt;
        &lt;ListenFor RequireAppName="ExplicitlySpecified"&gt; book [me] {builtin:AppName} a yyy in my favourite {favourite} &lt;/ListenFor&gt;
        &lt;Feedback&gt; Booking a yyy in my favourite {favourite} &lt;/Feedback&gt;
        &lt;Navigate /&gt;
      &lt;/Command&gt;
  
      &lt;PhraseList Label="favourite"&gt;
        &lt;Item&gt;home&lt;/Item&gt;
        &lt;Item&gt;work&lt;/Item&gt;
      &lt;/PhraseList&gt;
  
    &lt;/CommandSet&gt;
  
  &lt;/VoiceCommands&gt;
  </code></pre>
  
  <p>do you have any idea why this happen?
  thanks</p>