Fix NVDA screen reader incorrect list count for File menu separators (#2257)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: brianrob <6210322+brianrob@users.noreply.github.com>
Co-authored-by: Brian Robbins <brianrob@microsoft.com>

Author: Copilot

src/PerfView/MainWindow.xaml

@@ -29,7 +29,6 @@
         <CommandBinding Command="{x:Static src:MainWindow.MergeCommand}" Executed="DoMerge"/>
         <CommandBinding Command="{x:Static src:MainWindow.ZipCommand}" Executed="DoZip"/>
         <CommandBinding Command="{x:Static src:MainWindow.UnZipCommand}" Executed="DoUnZip"/>
-        <CommandBinding Command="{x:Static src:MainWindow.HideCommand}" Executed="DoHide" CanExecute="CanHide" />
         <CommandBinding Command="{x:Static src:MainWindow.UserCommand}" Executed="DoUserCommand"/>
         <CommandBinding Command="{x:Static src:MainWindow.RefreshDirCommand}" Executed="DoRefreshDir"/>
         <CommandBinding Command="{x:Static src:MainWindow.OpenCommand}" Executed="DoOpen"/>
@@ -79,9 +78,6 @@
                     <MenuItem Header="Set Symbol _Path" Click="DoSetSymbolPath" ToolTip="Sets the locations to look for symbolic information (PDB files)."/>
                     <MenuItem Header="_User Command" Command="{x:Static src:MainWindow.UserCommand}" ToolTip="Run a User Defined Command."/>
                     <MenuItem Header="Go to Directory" Command="{x:Static src:MainWindow.FocusDirectoryCommand}" ToolTip="Focus and select the directory textbox."/>
-                    <Separator/>
-                    <MenuItem Header="_Hide" Command="{x:Static src:MainWindow.HideCommand}" ToolTip="Hides the current window (can reopen using windows explorer)"/>
-                    <Separator/>
                     <MenuItem Header="_Exit" Click="DoExit"/>
                 </MenuItem>
                 <MenuItem Header="_Collect">

src/PerfView/MainWindow.xaml.cs

@@ -538,21 +538,6 @@ private void DoUnZip(object sender, RoutedEventArgs e)
             });
         }
 
-        private void DoHide(object sender, RoutedEventArgs e)
-        {
-            // TODO need count of all active children
-            if (StackWindow.StackWindows.Count > 0)
-            {
-                Visibility = Visibility.Hidden;
-            }
-        }
-
-        private void CanHide(object sender, CanExecuteRoutedEventArgs e)
-        {
-            // TODO need count of all active children
-            e.CanExecute = StackWindow.StackWindows.Count > 0;
-        }
-
         private void DoUserCommand(object sender, RoutedEventArgs e)
         {
             if (m_UserDefineCommandDialog == null)
@@ -1081,8 +1066,6 @@ private void Window_Closed(object sender, EventArgs e)
         public static RoutedUICommand UnZipCommand = new RoutedUICommand("UnZip", "UnZip", typeof(MainWindow));
         public static RoutedUICommand ItemHelpCommand = new RoutedUICommand("Help on Item", "ItemHelp", typeof(MainWindow));
         public static RoutedUICommand OpenInBrowserCommand = new RoutedUICommand("Open in Browser", "OpenInBrowser", typeof(MainWindow));
-        public static RoutedUICommand HideCommand = new RoutedUICommand("Hide", "Hide", typeof(MainWindow),
-            new InputGestureCollection() { new KeyGesture(Key.H, ModifierKeys.Alt) });
         public static RoutedUICommand UserCommand = new RoutedUICommand("User Command", "UserCommand", typeof(MainWindow),
     new InputGestureCollection() { new KeyGesture(Key.U, ModifierKeys.Alt) });
         public static RoutedUICommand RefreshDirCommand = new RoutedUICommand("Refresh Dir", "RefreshDir",