TF-4367 Add E2E test for test case forward email is forwarded when change language on mobile

integration_test/mixin/generate_email_scenario_mixin.dart

@@ -0,0 +1,29 @@
+import 'package:flutter_test/flutter_test.dart';
+
+import '../base/base_scenario.dart';
+import '../models/provisioning_email.dart';
+import '../robots/email_robot.dart';
+import 'scenario_utils_mixin.dart';
+
+mixin GenerateEmailScenarioMixin on BaseScenario, ScenarioUtilsMixin {
+  Future<void> generateEmailWithSubject({
+    required String emailUser,
+    required String subject,
+  }) async {
+    await provisionEmail(
+      [
+        ProvisioningEmail(
+          toEmail: emailUser,
+          subject: subject,
+          content: subject,
+        ),
+      ],
+      requestReadReceipt: false,
+    );
+    await $.pumpAndTrySettle();
+  }
+
+  Future<void> closeEmailDetailedView({required EmailRobot emailRobot}) async {
+    await emailRobot.onTapBackButton();
+  }
+}