title: Inner Accordion Item having issue expanding when there are too many items in outer Accordian
body: <p>I have below xaml code using accrodian. Basically issue is I am using two accordians one nested in other. Both are sheileded by ScrollViewer. If there are more than 14 items in the outer accordion then expanding inner one is not visible, means its getting expanded but because of no space its not visible.</p>
  
  <p>
      
          
             -- some code
          
      </p>
  
  <pre><code>&lt;toolkit:AccordionItem x:Name="test2" Style="{StaticResource ContentEditorAccordionItemStyle}" Header="{Binding LogicBlock, Source={StaticResource ResourceString}}" HorizontalAlignment="Stretch"&gt;
      &lt;ScrollViewer BorderBrush="Red" BorderThickness="2" Grid.Row="3" HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Auto" Style="{StaticResource ScrollViewerStyle}"&gt;
          &lt;toolkit:Accordion Grid.Row="1"  x:Name="testnew" ItemsSource="{Binding DynamicContentBlocks.Source, Mode=TwoWay}" FontSize="10" BorderBrush="{x:Null}"&gt;
              &lt;toolkit:Accordion.ItemTemplate&gt;
                  &lt;DataTemplate&gt;
                      &lt;Grid Margin="6,0"&gt;
                          &lt;TextBlock Style="{StaticResource DefaultTextBlockStyle}" Text="{Binding Name}" FontSize="10"/&gt;
                      &lt;/Grid&gt;
                  &lt;/DataTemplate&gt;
              &lt;/toolkit:Accordion.ItemTemplate&gt;
              &lt;toolkit:Accordion.ContentTemplate&gt;
                  &lt;DataTemplate&gt;
                      &lt;ScrollViewer HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Auto" 
                              Style="{StaticResource ScrollViewerStyle}"&gt; 
                          &lt;ItemsControl ItemsSource="{Binding Blocks}"&gt;
                              &lt;ItemsControl.ItemTemplate&gt;
                                  &lt;DataTemplate&gt;
  
                                      &lt;Grid&gt;
                                          &lt;Grid.RowDefinitions&gt;
                                              &lt;RowDefinition Height="6"/&gt;
                                              &lt;RowDefinition/&gt;
                                          &lt;/Grid.RowDefinitions&gt;
                                          &lt;CheckBox Grid.Row="1" x:Name="chkSelectItem" IsChecked="{Binding IsSelected, Mode=TwoWay}" 
                                      Style="{StaticResource DefaultCheckBoxStyle}" Content="{Binding Name}" FontSize="10" /&gt;
                                      &lt;/Grid&gt;
  
                                  &lt;/DataTemplate&gt;
                              &lt;/ItemsControl.ItemTemplate&gt;
                          &lt;/ItemsControl&gt;
                      &lt;/ScrollViewer&gt;
                  &lt;/DataTemplate&gt;
              &lt;/toolkit:Accordion.ContentTemplate&gt;
          &lt;/toolkit:Accordion&gt;
      &lt;/ScrollViewer&gt;
  &lt;/toolkit:AccordionItem&gt;
  &lt;toolkit:AccordionItem x:Name="test3" Style="{StaticResource ContentEditorAccordionItemStyle}" Header="{Binding DataR, Source={StaticResource ResourceString}}" HorizontalAlignment="Stretch"&gt;
      &lt;ScrollViewer Grid.Row="3" HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Auto" Style="{StaticResource ScrollViewerStyle}"&gt;
      -- some code
      &lt;/ScrollViewer&gt;
  &lt;/toolkit:AccordionItem&gt;
  </code></pre>
  
  <p></p>