Added Performance overlays in developer options

lib/main.dart

@@ -106,7 +106,12 @@ class _MainState extends State<Main> {
       textDirection: TextDirection.ltr,
       child: Consumer<SettingsProvider>(
         builder: (context, settings, child) {
+          var devToolsSettings = settings.val().devToolsSettings;
           return MaterialApp(
+            showPerformanceOverlay: devToolsSettings.showPerformanceOverlay,
+            checkerboardOffscreenLayers: devToolsSettings.checkerboardOffscreenLayers,
+            checkerboardRasterCacheImages: devToolsSettings.checkerboardRasterCacheImages,
+
             debugShowCheckedModeBanner: false,
             localizationsDelegates: const [
               ...GlobalMaterialLocalizations.delegates,