Merging.

shrine/lib/app.dart

@@ -15,10 +15,10 @@
 import 'package:flutter/material.dart';
 
 import 'backdrop.dart';
+import 'category_menu_page.dart';
 import 'colors.dart';
 import 'home.dart';
 import 'login.dart';
-import 'category_menu_page.dart';
 import 'model/product.dart';
 import 'supplemental/cut_corners_border.dart';
 

shrine/lib/backdrop.dart

@@ -19,7 +19,7 @@ import 'login.dart';
 import 'model/product.dart';
 import 'shopping_cart.dart';
 
-double _kFlingVelocity = 2.0;
+const double _kFlingVelocity = 2.0;
 
 class _FrontLayer extends StatelessWidget {
   const _FrontLayer({