[Extensions] Remove RequestSender::ScopedTabID

extensions/renderer/request_sender.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 EXTENSIONS_RENDERER_REQUEST_SENDER_H_
 #define EXTENSIONS_RENDERER_REQUEST_SENDER_H_
 
 #include <map>
 #include <string>
 
@@ skipping 29 matching lines @@
     virtual ~Source() {}
 
     virtual ScriptContext* GetContext() = 0;
     virtual void OnResponseReceived(const std::string& name,
                                     int request_id,
                                     bool success,
                                     const base::ListValue& response,
                                     const std::string& error) = 0;
   };
 
-  // Helper class to (re)set the |source_tab_id_| below.
-  class ScopedTabID {
-   public:
-    ScopedTabID(RequestSender* request_sender, int tab_id);
-    ~ScopedTabID();
-
-   private:
-    RequestSender* const request_sender_;
-    const int tab_id_;
-    const int previous_tab_id_;
-
-    DISALLOW_COPY_AND_ASSIGN(ScopedTabID);
-  };
-
   RequestSender();
   virtual ~RequestSender();
 
   // In order to avoid collision, all |request_id|s passed into StartRequest()
   // should be generated by this method.
   int GetNextRequestId() const;
 
   // Makes a call to the API function |name| that is to be handled by the
   // extension host. The response to this request will be received in
   // HandleResponse().
@@ skipping 27 matching lines @@
  private:
   friend class ScopedTabID;
   using PendingRequestMap = std::map<int, std::unique_ptr<PendingRequest>>;
 
   void InsertRequest(int request_id,
                      std::unique_ptr<PendingRequest> pending_request);
   std::unique_ptr<PendingRequest> RemoveRequest(int request_id);
 
   PendingRequestMap pending_requests_;
 
-  int source_tab_id_;  // Id of the tab sending the request, or -1 if no tab.
-
   DISALLOW_COPY_AND_ASSIGN(RequestSender);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_RENDERER_REQUEST_SENDER_H_