[I suspect this is the same as SRCTREEWIN-3028]

Setup: Unstaged view in tree mode, multiple files in unstaged view, nothing in staged view.

1. Click top-level checkbox to stage everything
2. As soon as files move to staged view, click that top-level checkbox to unstage everything
3. As soon as files move back to unstaged view, shift-click to multi-select files (since the first file should already be selected)

This has fairly consistently, but not 100% consistently, crashed. Timing seems relevant. Guessing a race condition between the interaction and updating the views.

Relevant exception:
2015-07-19T13:43:42: Fatal error:
System.InvalidOperationException: Sequence contains no elements

2015-07-19T13:43:42: Stack trace:
at System.Linq.Enumerable.First[TSource](IEnumerable`1 source)
at System.Windows.Controls.SelectionMultiple.SelectCore(MultiSelectTreeViewItem item) in C:\projects\bitbucket.org\atlassian\sourcetreewin\Dependencies\MultiSelectTreeView\Controls\SelectionMultiple.cs:line 144
at System.Windows.Controls.MultiSelectTreeViewItem.OnMouseDown(MouseButtonEventArgs e) in C:\projects\bitbucket.org\atlassian\sourcetreewin\Dependencies\MultiSelectTreeView\Controls\MultiSelectTreeViewItem.cs:line 735
at System.Windows.UIElement.OnMouseDownThunk(Object sender, MouseButtonEventArgs e)
at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs)
at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
at System.Windows.ContentElement.RaiseTrustedEvent(RoutedEventArgs args)
at System.Windows.Input.InputManager.ProcessStagingArea()
at System.Windows.Input.InputProviderSite.ReportInput(InputReport inputReport)
at System.Windows.Interop.HwndMouseInputProvider.ReportInput(IntPtr hwnd, InputMode mode, Int32 timestamp, RawMouseActions actions, Int32 x, Int32 y, Int32 wheel)
at System.Windows.Interop.HwndMouseInputProvider.FilterMessage(IntPtr hwnd, WindowMessage msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
at System.Windows.Interop.HwndSource.InputFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)