Prevent tabs sync during browser shutdown.

components/sync_sessions/sessions_sync_manager.h

 // 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.
 
 #ifndef COMPONENTS_SYNC_SESSIONS_SESSIONS_SYNC_MANAGER_H_
 #define COMPONENTS_SYNC_SESSIONS_SESSIONS_SYNC_MANAGER_H_
 
 #include <stddef.h>
 
 #include <map>
@@ skipping 83 matching lines @@
   bool GetForeignSessionTabs(
       const std::string& tag,
       std::vector<const sessions::SessionTab*>* tabs) override;
   void DeleteForeignSession(const std::string& tag) override;
   bool GetLocalSession(const SyncedSession** local_session) override;
 
   // LocalSessionEventHandler implementation.
   void OnLocalTabModified(SyncedTabDelegate* modified_tab) override;
   void OnFaviconsChanged(const std::set<GURL>& page_urls,
                          const GURL& icon_url) override;
+  void SetAllBrowsersClosing(bool browsers_closing) override;
+
+  bool GetAllBrowsersClosingForTesting();
+  static void SetInitialAllBrowsersClosingValueForTesting(
+      bool initial_browsers_closing);
 
   // Returns the tag used to uniquely identify this machine's session in the
   // sync model.
   const std::string& current_machine_tag() const {
     DCHECK(!current_machine_tag_.empty());
     return current_machine_tag_;
   }
 
   FaviconCache* GetFaviconCache();
 
@@ skipping 165 matching lines @@
 
   // Tracks whether our local representation of which sync nodes map to what
   // tabs (belonging to the current local session) is inconsistent.  This can
   // happen if a foreign client deems our session as "stale" and decides to
   // delete it. Rather than respond by bullishly re-creating our nodes
   // immediately, which could lead to ping-pong sequences, we give the benefit
   // of the doubt and hold off until another local navigation occurs, which
   // proves that we are still relevant.
   bool local_tab_pool_out_of_sync_;
 
+  // Indicates that browsers are closing, so we shouldn't sync tabs closing
+  // events.
+  bool all_browsers_closing_;
+
   syncer::SyncPrefs* sync_prefs_;
 
   std::unique_ptr<syncer::SyncErrorFactory> error_handler_;
   std::unique_ptr<syncer::SyncChangeProcessor> sync_processor_;
 
   // Local device info provider, owned by ProfileSyncService.
   const syncer::LocalDeviceInfoProvider* const local_device_;
 
   // Unique client tag.
   std::string current_machine_tag_;
@@ skipping 23 matching lines @@
 
   // Callback to inform sync that a sync data refresh is requested.
   base::Closure datatype_refresh_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(SessionsSyncManager);
 };
 
 }  // namespace sync_sessions
 
 #endif  // COMPONENTS_SYNC_SESSIONS_SESSIONS_SYNC_MANAGER_H_