title: ListBox.ScrollIntoView() does not seem to work in WP7
body: <p>I want to move the listbox scrollbar to the bottom whenever a new item is added to the itemssource, but <code>ScrollIntoView()</code> doesn't seem to do anything if I pass it either a reference to the newly added item, or the index of it. Has anyone gotten this to work, or have any other suggestions as to how I could scroll the listbox down to the bottom?</p>
  
  <p>Some code:</p>
  
  <pre><code>    void Actions_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
      {
          //if a new item was added, set it to the selected item
          if (e.NewItems != null)
          {
              MainListBox.SelectedIndex = e.NewStartingIndex;
  
              //MainListBox.ScrollIntoView(MainListBox.Items.Last());     //todo: this doesnt seem to work
          }
      }
  </code></pre>