Created Unassigned: AvalonDock using Ctrl-Tab does not focus the selected item [22499]

When using ctrl-tab and selecting a docked item, it's not given focus.

Repro using the code below:

* Select text in both Anchorable1 and Anchorable2
* Ctrl-Tab and select Anchorable2
Expected:
Anchorable2 ListView selected item has focus

Actual:
Anchorable1 ListView selected item retains focus

```<Window x:Class="AvalonDockFocus.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:AvalonDockFocus"
xmlns:xcad="http://schemas.xceed.com/wpf/xaml/avalondock"
mc:Ignorable="d"
Title="MainWindow" Height="350" Width="525">
<xcad:DockingManager>
<xcad:LayoutRoot>
<xcad:LayoutPanel>
<xcad:LayoutAnchorablePaneGroup Orientation="Horizontal">
<xcad:LayoutAnchorablePane>
<xcad:LayoutAnchorable Title="Anchorable1">
<ListView>
<ListView.Items>
<TextBlock Text="a" />
<TextBlock Text="b" />
<TextBlock Text="c" />
</ListView.Items>
</ListView>
</xcad:LayoutAnchorable>
</xcad:LayoutAnchorablePane>
<xcad:LayoutAnchorablePane>
<xcad:LayoutAnchorable Title="Anchorable2">
<ListView>
<ListView.Items>
<TextBlock Text="a" />
<TextBlock Text="b" />
<TextBlock Text="c" />
</ListView.Items>
</ListView>
</xcad:LayoutAnchorable>
</xcad:LayoutAnchorablePane>
</xcad:LayoutAnchorablePaneGroup>
</xcad:LayoutPanel>
</xcad:LayoutRoot>
</xcad:DockingManager>
</Window>
```