Get signals working in the EXTRA_DATA section of MHTML

components/offline_pages/core/stub_offline_page_model.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/offline_pages/core/stub_offline_page_model.h"
 
 namespace offline_pages {
 
 StubOfflinePageModel::StubOfflinePageModel() {}
 StubOfflinePageModel::~StubOfflinePageModel() {}
 
 void StubOfflinePageModel::AddObserver(Observer* observer) {}
 void StubOfflinePageModel::RemoveObserver(Observer* observer) {}
 void StubOfflinePageModel::SavePage(
     const SavePageParams& save_page_params,
     std::unique_ptr<OfflinePageArchiver> archiver,
+    const std::vector<std::string>& signal_data,
     const SavePageCallback& callback) {}
 void StubOfflinePageModel::MarkPageAccessed(int64_t offline_id) {}
 void StubOfflinePageModel::DeletePagesByOfflineId(
     const std::vector<int64_t>& offline_ids,
     const DeletePageCallback& callback) {}
 void StubOfflinePageModel::DeletePagesByClientIds(
     const std::vector<ClientId>& client_ids,
     const DeletePageCallback& callback) {}
 void StubOfflinePageModel::GetPagesMatchingQuery(
     std::unique_ptr<OfflinePageModelQuery> query,
@@ skipping 22 matching lines @@
 ClientPolicyController* StubOfflinePageModel::GetPolicyController() {
   return &policy_controller_;
 }
 bool StubOfflinePageModel::is_loaded() const {
   return true;
 }
 OfflineEventLogger* StubOfflinePageModel::GetLogger() {
   return nullptr;
 }
 }  // namespace offline_pages