[Offline Pages] Removes two-step expiration related.

components/offline_pages/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/downloads/download_ui_adapter.h"
 
 #include "base/bind.h"
 #include "base/guid.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
@@ skipping 105 matching lines @@
 }
 
 void DownloadUIAdapter::DeleteItem(const std::string& guid) {
   // TODO(dimich): Also remove pending request from RequestQueue.
   DownloadUIItems::const_iterator it = items_.find(guid);
   if (it == items_.end())
     return;
 
   std::vector<int64_t> page_ids;
   page_ids.push_back(it->second->offline_id);
-  // TODO(dimich): This should be ExpirePages(...Now()..) when Expire is
-  // firing Observer method. The resulting Observer notification will update
-  // local cache.
   model_->DeletePagesByOfflineId(
       page_ids, base::Bind(&DownloadUIAdapter::OnDeletePagesDone,
                            weak_ptr_factory_.GetWeakPtr()));
 }
 
 int64_t DownloadUIAdapter::GetOfflineIdByGuid(
     const std::string& guid) const {
   // TODO(dimich): when requests are also in the cache, filter them out.
   // Requests do not yet have offline ID.
   DownloadUIItems::const_iterator it = items_.find(guid);
@@ skipping 72 matching lines @@
   // TODO(dimich): Consider adding UMA to record user actions.
 }
 
 bool DownloadUIAdapter::IsVisibleInUI(const ClientId& client_id) {
   const std::string& name_space = client_id.name_space;
   return model_->GetPolicyController()->IsSupportedByDownload(name_space) &&
          base::IsValidGUID(client_id.id);
 }
 
 }  // namespace offline_pages