TF-2528 Add integration test for search email with sort by sender nam…e ascending

integration_test/base/base_scenario.dart

@@ -1,3 +1,4 @@
+import 'package:flutter_test/flutter_test.dart';
 import 'package:patrol/patrol.dart';
 
 abstract class BaseScenario {
@@ -6,4 +7,9 @@ abstract class BaseScenario {
   const BaseScenario(this.$);
 
   Future<void> execute();
+
+  Future<void> expectViewVisible(PatrolFinder patrolFinder) async {
+    await $.waitUntilVisible(patrolFinder);
+    expect(patrolFinder, findsWidgets);
+  }
 }