Fixes to enable indication of bytes downloaded for Offline Pages in Download Home.

components/offline_pages/core/downloads/download_ui_adapter.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/downloads/download_ui_adapter.h"
 
 #include "base/bind.h"
 #include "base/guid.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "components/offline_pages/core/background/request_coordinator.h"
 #include "components/offline_pages/core/background/save_page_request.h"
 #include "components/offline_pages/core/client_namespace_constants.h"
 #include "components/offline_pages/core/client_policy_controller.h"
 #include "components/offline_pages/core/downloads/download_ui_item.h"
 #include "components/offline_pages/core/offline_page_model.h"
 
+namespace {
+// Value of this constant doesn't matter, only its address is used.
+const char kDownloadUIAdapterKey[] = "";
+}
+
 namespace offline_pages {
 
+// static
+DownloadUIAdapter* DownloadUIAdapter::FromOfflinePageModel(
+    OfflinePageModel* model) {
+  DCHECK(model);
+  return static_cast<DownloadUIAdapter*>(
+      model->GetUserData(kDownloadUIAdapterKey));
+}
+
+// static
+void DownloadUIAdapter::AttachToOfflinePageModel(DownloadUIAdapter* adapter,
+                                                 OfflinePageModel* model) {
+  DCHECK(adapter);
+  DCHECK(model);
+  model->SetUserData(kDownloadUIAdapterKey, adapter);
+}
+
 DownloadUIAdapter::ItemInfo::ItemInfo(const OfflinePageItem& page)
     : ui_item(base::MakeUnique<DownloadUIItem>(page)),
       is_request(false),
       offline_id(page.offline_id),
       client_id(page.client_id),
       temporarily_hidden(false) {}
 
 DownloadUIAdapter::ItemInfo::ItemInfo(const SavePageRequest& request)
     : ui_item(base::MakeUnique<DownloadUIItem>(request)),
       is_request(true),
@@ skipping 286 matching lines @@
   items_.erase(it);
 
   if (state_ != State::LOADED)
     return;
 
   for (Observer& observer : observers_)
     observer.ItemDeleted(guid);
 }
 
 }  // namespace offline_pages