Enable to show the keyboard overlay by shortcut key.

chrome/browser/ui/browser.h

 // Copyright (c) 2010 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_BROWSER_H_
 #define CHROME_BROWSER_UI_BROWSER_H_
 #pragma once
 
 #include <map>
 #include <set>
@@ skipping 441 matching lines @@
   void SelectLastTab();
   void DuplicateTab();
   void WriteCurrentURLToClipboard();
   void ConvertPopupToTabbedBrowser();
   // In kiosk mode, the first toggle is valid, the rest is discarded.
   void ToggleFullscreenMode();
   void Exit();
 #if defined(OS_CHROMEOS)
   void ToggleCompactNavigationBar();
   void Search();
+  void ShowKeyboardOverlay();
 #endif
 
   // Page-related commands
   void BookmarkCurrentPage();
   void SavePage();
   void ViewSource();
   void ShowFindBar();
 
   // Returns true if the Browser supports the specified feature. The value of
   // this varies during the lifetime of the browser. For example, if the window
@@ skipping 635 matching lines @@
   // The profile's tab restore service. The service is owned by the profile,
   // and we install ourselves as an observer.
   TabRestoreService* tab_restore_service_;
 
   scoped_ptr<InstantController> instant_;
 
   DISALLOW_COPY_AND_ASSIGN(Browser);
 };
 
 #endif  // CHROME_BROWSER_UI_BROWSER_H_