[fenix] For https://github.com/mozilla-mobile/fenix/issues/10848 - Fixes tab tray colors

app/src/main/java/org/mozilla/fenix/tabtray/TabTrayViewHolder.kt

@@ -145,15 +145,15 @@ class TabTrayViewHolder(itemView: View) : TabViewHolder(itemView) {
 
     @VisibleForTesting
     internal fun updateBackgroundColor(isSelected: Boolean) {
-        val itemBackground = if (isSelected) {
-            R.attr.tabTrayItemSelectedBackground
+        val color = if (isSelected) {
+            R.color.tab_tray_item_selected_background_normal_theme
         } else {
-            R.attr.tabTrayItemBackground
+            R.color.tab_tray_item_background_normal_theme
         }
         itemView.setBackgroundColor(
             ContextCompat.getColor(
                 itemView.context,
-                ThemeManager.resolveAttribute(itemBackground, itemView.context)
+                color
             )
         )
     }

app/src/main/res/drawable/tab_tray_divider.xml

@@ -6,7 +6,7 @@
 
     <shape>
         <size android:height="1dp"/>
-        <solid android:color="?tabTrayItemDivider" />
+        <solid android:color="@color/tab_tray_item_divider_normal_theme" />
     </shape>
 
 </inset>