[Extensions] Remove source/opener tab id from extension ports

chrome/browser/extensions/api/messaging/extension_message_port.h

 // Copyright (c) 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_EXTENSIONS_API_MESSAGING_EXTENSION_MESSAGE_PORT_H_
 #define CHROME_BROWSER_EXTENSIONS_API_MESSAGING_EXTENSION_MESSAGE_PORT_H_
 
 #include "base/macros.h"
 #include "chrome/browser/extensions/api/messaging/message_service.h"
 
@@ skipping 80 matching lines @@
   // Only for receivers in an extension process.
   content::RenderProcessHost* extension_process_;
 
   // When the port is used as a sender, this set contains only one element.
   // If used as a receiver, it may contain any number of frames.
   // This set is populated before the first message is sent to the destination,
   // and shrinks over time when the port is rejected by the recipient frame, or
   // when the frame is removed or unloaded.
   std::set<content::RenderFrameHost*> frames_;
 
-  // The ID of the tab where the channel was created. This is saved so that any
-  // onMessage events can be run in the scope of the tab.
-  // Only set on receiver ports (if the opener was a tab). -1 if invalid.
-  int opener_tab_id_;
-
   // Whether the renderer acknowledged creation of the port. This is used to
   // distinguish abnormal port closure (e.g. no receivers) from explicit port
   // closure (e.g. by the port.disconnect() JavaScript method in the renderer).
   bool did_create_port_;
 
   ExtensionHost* background_host_ptr_;  // used in IncrementLazyKeepaliveCount
   std::unique_ptr<FrameTracker> frame_tracker_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionMessagePort);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_MESSAGING_EXTENSION_MESSAGE_PORT_H_