Fix restoration of search details page

Author: goderbauer

experimental/veggieseasons/lib/screens/search.dart

@@ -99,21 +99,24 @@ class _SearchScreenState extends State<SearchScreen> with RestorationMixin {
     final model = Provider.of<AppState>(context);
 
     return UnmanagedRestorationScope(
+      bucket: bucket,
       child: CupertinoTabView(
+        restorationScopeId: 'tabview',
         builder: (context) {
           return AnnotatedRegion<SystemUiOverlayStyle>(
-              value: SystemUiOverlayStyle(
-                  statusBarBrightness:
-                      MediaQuery.platformBrightnessOf(context)),
-              child: SafeArea(
-                bottom: false,
-                child: Stack(
-                  children: [
-                    _buildSearchResults(model.searchVeggies(terms)),
-                    _createSearchBox(),
-                  ],
-                ),
-              ));
+            value: SystemUiOverlayStyle(
+              statusBarBrightness: MediaQuery.platformBrightnessOf(context),
+            ),
+            child: SafeArea(
+              bottom: false,
+              child: Stack(
+                children: [
+                  _buildSearchResults(model.searchVeggies(terms)),
+                  _createSearchBox(),
+                ],
+              ),
+            ),
+          );
         },
       ),
     );

experimental/veggieseasons/test/restoration_test.dart

@@ -121,6 +121,29 @@ void main() {
     expect(find.text('Tangelo'), findsOneWidget);
     expect(find.text('Tan').hitTestable(), findsOneWidget); // search text
 
+    expect(find.text('Serving info'), findsNothing);
+
+    // Open a details page from search
+    await tester.tap(find.text('Tangelo'));
+    await tester.pumpAndSettle();
+
+    expect(find.text('Tangelo'), findsOneWidget);
+    expect(find.text('Serving info'), findsOneWidget);
+    
+    // Restores details page
+    await tester.restartAndRestore();
+    expect(find.text('Tangelo'), findsOneWidget);
+    expect(find.text('Serving info'), findsOneWidget);
+
+    // Go back to search page, is also restored
+    tester.state<NavigatorState>(find.byType(Navigator).last).pop();
+    await tester.pumpAndSettle();
+
+    expect(find.text('Serving info'), findsNothing);
+    expect(find.text('Apples'), findsNothing);
+    expect(find.text('Tangelo'), findsOneWidget);
+    expect(find.text('Tan').hitTestable(), findsOneWidget); // search text
+
     expect(find.text('Calorie Target'), findsNothing);
 
     // Go to "Settings".