Enable to show the keyboard overlay by shortcut key.

chrome/browser/ui/browser_window.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_WINDOW_H_
 #define CHROME_BROWSER_UI_BROWSER_WINDOW_H_
 #pragma once
 
 #include "chrome/browser/tab_contents/navigation_entry.h"
 #include "chrome/common/content_settings_types.h"
@@ skipping 312 matching lines @@
   virtual void ShowInstant(TabContents* preview_contents) = 0;
 
   // Invoked when the instant's tab contents should be hidden.
   virtual void HideInstant() = 0;
 
   // Returns the desired bounds for instant in screen coordinates. Note that if
   // instant isn't currently visible this returns the bounds instant would be
   // placed at.
   virtual gfx::Rect GetInstantBounds() = 0;
 
+#if defined(OS_CHROMEOS)
+  // Shows the keyboard overlay dialog box.
+  virtual void ShowKeyboardOverlay(gfx::NativeWindow owning_window) = 0;
+#endif
+
   // Construct a BrowserWindow implementation for the specified |browser|.
   static BrowserWindow* CreateBrowserWindow(Browser* browser);
 
   // Construct a FindBar implementation for the specified |browser|.
   static FindBar* CreateFindBar(Browser* browser_window);
 
  protected:
   friend class BrowserList;
   friend class BrowserView;
   virtual void DestroyBrowser() = 0;
@@ skipping 29 matching lines @@
 
   // Returns the ToolbarView.
   virtual ToolbarView* GetToolbarView() const = 0;
 #endif
 
  protected:
   virtual ~BrowserWindowTesting() {}
 };
 
 #endif  // CHROME_BROWSER_UI_BROWSER_WINDOW_H_