Avalonia - Add border to Flyouts (#3341)

* add borders to menus

* apply to dropdowns

* darken the border for dark theme

* fix duplicate keys

Ryujinx.Ava/Assets/Styles/BaseDark.xaml

@@ -54,5 +54,6 @@
         <Color x:Key="TextOnAccentFillColorPrimary">#FFFFFFFF</Color>
         <Color x:Key="SystemChromeWhiteColor">#FFFFFFFF</Color>
         <Color x:Key="ThemeForegroundColor">#FFFFFFFF</Color>
+        <Color x:Key="MenuFlyoutPresenterBorderColor">#3D3D3D</Color>
     </Styles.Resources>
 </Styles>

Ryujinx.Ava/Assets/Styles/BaseLight.xaml

@@ -49,5 +49,6 @@
         <Color x:Key="TextOnAccentFillColorPrimary">#FFFFFFFF</Color>
         <Color x:Key="SystemChromeWhiteColor">#FFFFFFFF</Color>
         <Color x:Key="ThemeForegroundColor">#FF000000</Color>
+        <Color x:Key="MenuFlyoutPresenterBorderColor">#C1C1C1</Color>
     </Styles.Resources>
 </Styles>

Ryujinx.Ava/Assets/Styles/Styles.xaml

@@ -221,6 +221,7 @@
         <Setter Property="Foreground" Value="{DynamicResource ThemeForegroundColor}" />
     </Style>
     <Styles.Resources>
+        <SolidColorBrush x:Key="ThemeAccentColorBrush" Color="{DynamicResource SystemAccentColor}" />
         <StaticResource x:Key="ListViewItemBackgroundSelected" ResourceKey="ThemeAccentColorBrush" />
         <StaticResource x:Key="ListViewItemBackgroundPressed" ResourceKey="SystemAccentColorDark1" />
         <StaticResource x:Key="ListViewItemBackgroundPointerOver" ResourceKey="SystemAccentColorDark2" />
@@ -232,7 +233,7 @@
             Color="{DynamicResource SystemBaseMediumLowColor}" />
         <SolidColorBrush x:Key="DataGridSelectionBackgroundBrush" Color="{DynamicResource DataGridSelectionColor}" />
         <SolidColorBrush x:Key="MenuFlyoutPresenterBorderBrush" Color="{DynamicResource MenuFlyoutPresenterBorderColor}" />
-        <SolidColorBrush x:Key="ThemeAccentColorBrush" Color="{DynamicResource SystemAccentColor}" />
+        <SolidColorBrush x:Key="FlyoutBorderThemeBrush" Color="{DynamicResource MenuFlyoutPresenterBorderColor}" />
         <SolidColorBrush x:Key="ListBoxBackground" Color="{DynamicResource ThemeContentBackgroundColor}" />
         <SolidColorBrush x:Key="ThemeForegroundBrush" Color="{DynamicResource ThemeForegroundColor}" />
         <SolidColorBrush x:Key="ThemeAccentBrush4" Color="{DynamicResource ThemeAccentColor4}" />