[Autofill Assistant] Add information on missing username for the chosen login option

Bug: b/157457785
Change-Id: I405f33df3d48af3a83edfd58ebf6bb8fe29c08fd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2390644Reviewed-by: Mathias Carlen <mcarlen@chromium.org>
Commit-Queue: Michele Mancina <micantox@google.com>
Cr-Commit-Position: refs/heads/master@{#804156}

components/autofill_assistant/browser/actions/collect_user_data_action.cc

@@ -1131,6 +1131,10 @@ void CollectUserDataAction::WriteProcessedAction(UserData* user_data,
     if (login_details != login_details_map_.end()) {
       if (login_details->second->login.has_value()) {
         user_data->selected_login_ = *login_details->second->login;
+        if (login_details->second->login->username.empty()) {
+          processed_action_proto_->mutable_collect_user_data_result()
+              ->set_login_missing_username(true);
+        }
       }
 
       processed_action_proto_->mutable_collect_user_data_result()

components/autofill_assistant/browser/actions/collect_user_data_action_unittest.cc

@@ -313,6 +313,50 @@ TEST_F(CollectUserDataActionTest, SelectLogin) {
   action.ProcessAction(callback_.Get());
 }
 
+TEST_F(CollectUserDataActionTest, SelectLoginMissingUsername) {
+  ActionProto action_proto;
+  auto* collect_user_data_proto = action_proto.mutable_collect_user_data();
+  collect_user_data_proto->set_request_terms_and_conditions(false);
+  auto* login_details = collect_user_data_proto->mutable_login_details();
+  auto* login_option = login_details->add_login_options();
+  login_option->mutable_password_manager();
+  login_option->set_payload("payload");
+
+  ON_CALL(mock_website_login_manager_, OnGetLoginsForUrl(_, _))
+      .WillByDefault(RunOnceCallback<1>(std::vector<WebsiteLoginManager::Login>{
+          WebsiteLoginManager::Login(GURL(kFakeUrl), /*username=*/"")}));
+  // Action should fetch the logins, but not the passwords.
+  EXPECT_CALL(mock_website_login_manager_, OnGetLoginsForUrl(GURL(kFakeUrl), _))
+      .Times(1);
+  EXPECT_CALL(mock_website_login_manager_, OnGetPasswordForLogin(_, _))
+      .Times(0);
+
+  ON_CALL(mock_action_delegate_, CollectUserData(_))
+      .WillByDefault(
+          Invoke([this](CollectUserDataOptions* collect_user_data_options) {
+            user_data_.succeed_ = true;
+            user_data_.login_choice_identifier_.assign(
+                collect_user_data_options->login_choices[0].identifier);
+            std::move(collect_user_data_options->confirm_callback)
+                .Run(&user_data_, &user_model_);
+          }));
+
+  EXPECT_CALL(
+      callback_,
+      Run(Pointee(AllOf(
+          Property(&ProcessedActionProto::status, ACTION_APPLIED),
+          Property(
+              &ProcessedActionProto::collect_user_data_result,
+              Property(&CollectUserDataResultProto::login_payload, "payload")),
+          Property(&ProcessedActionProto::collect_user_data_result,
+                   Property(&CollectUserDataResultProto::shown_to_user, true)),
+          Property(&ProcessedActionProto::collect_user_data_result,
+                   Property(&CollectUserDataResultProto::login_missing_username,
+                            true))))));
+  CollectUserDataAction action(&mock_action_delegate_, action_proto);
+  action.ProcessAction(callback_.Get());
+}
+
 TEST_F(CollectUserDataActionTest, LoginChoiceAutomaticIfNoOtherOptions) {
   ActionProto action_proto;
   auto* collect_user_data_proto = action_proto.mutable_collect_user_data();

components/autofill_assistant/browser/service.proto

@@ -543,6 +543,8 @@ message CollectUserDataResultProto {
   // Indicates whether the UI was shown to the user. This can be false if
   // only the login section was requested and the choice was implicitly made.
   optional bool shown_to_user = 16;
+  // Indicates that the chosen login option was missing the username.
+  optional bool login_missing_username = 17;
 
   reserved 7, 8;
 }