[Sync] Removing complexity around PROXY_TABS now that empty sessions are provided when disabled.

chrome/browser/ui/webui/foreign_session_handler.h

 // Copyright 2012 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 CHROME_BROWSER_UI_WEBUI_FOREIGN_SESSION_HANDLER_H_
 #define CHROME_BROWSER_UI_WEBUI_FOREIGN_SESSION_HANDLER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 43 matching lines @@
   // Returns a pointer to the current session model associator or NULL.
   static sync_sessions::OpenTabsUIDelegate* GetOpenTabsUIDelegate(
       content::WebUI* web_ui);
 
  private:
   // syncer::SyncServiceObserver:
   void OnStateChanged() override {}
   void OnSyncConfigurationCompleted() override;
   void OnForeignSessionUpdated() override;
 
-  // Returns true if tab sync is enabled for this profile, otherwise false.
-  bool IsTabSyncEnabled();
-
   // Returns a string used to show the user when a session was last modified.
   base::string16 FormatSessionTime(const base::Time& time);
 
   // Determines which session is to be opened, and then calls
   // OpenForeignSession, to begin the process of opening a new browser window.
   // This is a javascript callback handler.
   void HandleOpenForeignSession(const base::ListValue* args);
 
   // Determines whether foreign sessions should be obtained from the sync model.
   // This is a javascript callback handler, and it is also called when the sync
@@ skipping 15 matching lines @@
   // The time at which this WebUI was created. Used to calculate how long
   // the WebUI was present before the sessions data was visible.
   base::TimeTicks load_attempt_time_;
 
   DISALLOW_COPY_AND_ASSIGN(ForeignSessionHandler);
 };
 
 }  // namespace browser_sync
 
 #endif  // CHROME_BROWSER_UI_WEBUI_FOREIGN_SESSION_HANDLER_H_