Removes BrowserFrame::TabStripDisplayModeChanged, its long dead.

chrome/browser/ui/views/frame/native_browser_frame.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_UI_VIEWS_FRAME_NATIVE_BROWSER_FRAME_H_
 #define CHROME_BROWSER_UI_VIEWS_FRAME_NATIVE_BROWSER_FRAME_H_
 
 class BrowserFrame;
 class BrowserView;
 
@@ skipping 11 matching lines @@
   // Returns true if the OS takes care of showing the system menu. Returning
   // false means BrowserFrame handles showing the system menu.
   virtual bool UsesNativeSystemMenu() const = 0;
 
  protected:
   friend class BrowserFrame;
 
   // BrowserFrame pass-thrus ---------------------------------------------------
   // See browser_frame.h for documentation:
   virtual int GetMinimizeButtonOffset() const = 0;
-  // TODO(beng): replace with some kind of "framechanged" signal to Window.
-  virtual void TabStripDisplayModeChanged() = 0;
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_FRAME_NATIVE_BROWSER_FRAME_H_