[Sync] Introduce SyncedSessionWindow type.

ios/chrome/browser/ui/ntp/recent_tabs/synced_sessions.mm

 // Copyright 2014 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 "ios/chrome/browser/ui/ntp/recent_tabs/synced_sessions.h"
 
 #include <functional>
 #include <memory>
 
 #include "base/logging.h"
@@ skipping 88 matching lines @@
     // Order tabs by recency.
     std::vector<const sessions::SessionTab*> session_tabs;
     open_tabs->GetForeignSessionTabs(synced_session->session_tag,
                                      &session_tabs);
     for (const auto* session_tab : session_tabs) {
       AddTabToDistantSession(*session_tab, synced_session->session_tag, this);
     }
   } else {
     // Order tabs by their visual position within window.
     for (const auto& kv : synced_session->windows) {
-      for (const auto& session_tab : kv.second->tabs) {
+      for (const auto& session_tab : kv.second->wrapped_window.tabs) {
         AddTabToDistantSession(*session_tab, synced_session->session_tag, this);
       }
     }
   }
 }
 
 SyncedSessions::SyncedSessions() {}
 
 SyncedSessions::SyncedSessions(syncer::SyncService* sync_service) {
   DCHECK(sync_service);
@@ skipping 47 matching lines @@
   DCHECK_LE(index, GetSessionCount());
   sessions_.erase(sessions_.begin() + index);
 }
 
 void SyncedSessions::AddDistantSessionForTest(
     std::unique_ptr<const DistantSession> distant_session) {
   sessions_.push_back(std::move(distant_session));
 }
 
 }  // synced_sessions namespace