[fenix] For https://github.com/mozilla-mobile/fenix/issues/22800 - Remove unused tabTrayItemBackground attribute

app/src/main/res/values/attrs.xml

@@ -64,7 +64,6 @@
     <attr name="tabTrayThumbnailItemBackground" format="reference" />
     <attr name="tabTrayThumbnailIcon" format="reference" />
     <!-- Note - these are currently unused, but they are for if/when we add private UI to tabs tray -->
-    <attr name="tabTrayItemBackground" format="reference" />
     <attr name="tabTrayItemSelectedBackground" format="reference" />
     <attr name="tabTrayToolbarBackground" format="reference" />
 

app/src/main/res/values/styles.xml

@@ -90,7 +90,6 @@
         <item name="mozac_widget_favicon_background_color">@color/mozac_widget_favicon_background_normal_theme</item>
         <item name="mozac_widget_favicon_border_color">@color/mozac_widget_favicon_border_normal_theme</item>
 
-        <item name="tabTrayItemBackground">@color/tab_tray_item_background_normal_theme</item>
         <item name="tabTrayItemSelectedBackground">@color/tab_tray_item_selected_background_normal_theme</item>
         <item name="tabTrayToolbarBackground">@color/tab_tray_toolbar_background_normal_theme</item>
         <item name="tabTrayItemMediaBackground">@color/tab_tray_item_media_background_normal_theme</item>
@@ -276,7 +275,6 @@
         <item name="mozac_widget_favicon_border_color">@color/mozac_widget_favicon_border_private_theme</item>
 
         <!-- Tab Tray -->
-        <item name="tabTrayItemBackground">@color/tab_tray_item_background_normal_theme</item>
         <item name="tabTrayItemSelectedBackground">@color/tab_tray_item_selected_background_private_theme</item>
         <item name="tabTrayToolbarBackground">@color/tab_tray_toolbar_background_private_theme</item>
         <item name="tabTrayItemMediaBackground">@color/tab_tray_item_media_background_private_theme</item>