Implement the new Sync Confirmation dialog on Linux and Windows.

chrome/browser/ui/cocoa/browser_window_cocoa.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_COCOA_BROWSER_WINDOW_COCOA_H_
 #define CHROME_BROWSER_UI_COCOA_BROWSER_WINDOW_COCOA_H_
 
 #include "base/mac/scoped_nsobject.h"
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/extensions/extension_keybinding_registry.h"
@@ skipping 147 matching lines @@
   FindBar* CreateFindBar() override;
   web_modal::WebContentsModalDialogHost* GetWebContentsModalDialogHost()
       override;
   void ShowAvatarBubbleFromAvatarButton(
       AvatarBubbleMode mode,
       const signin::ManageAccountsParams& manage_accounts_params,
       signin_metrics::AccessPoint access_point) override;
   void ShowModalSigninWindow(AvatarBubbleMode mode,
                              signin_metrics::AccessPoint access_point) override;
   void CloseModalSigninWindow() override;
+  void ShowModalSyncConfirmationWindow();
   int GetRenderViewHeightInsetWithDetachedBookmarkBar() override;
   void ExecuteExtensionCommand(const extensions::Extension* extension,
                                const extensions::Command& command) override;
   ExclusiveAccessContext* GetExclusiveAccessContext() override;
 
   // ExclusiveAccessContext interface
   Profile* GetProfile() override;
   content::WebContents* GetActiveWebContents() override;
   void UnhideDownloadShelf() override;
   void HideDownloadShelf() override;
@@ skipping 35 matching lines @@
   ui::WindowShowState initial_show_state_;
   NSInteger attention_request_id_;  // identifier from requestUserAttention
 
   // Preserves window media state to show appropriate icon in the window title
   // which can be audio playing, muting or none (determined by media state of
   // tabs.
   TabMediaState media_state_;
 };
 
 #endif  // CHROME_BROWSER_UI_COCOA_BROWSER_WINDOW_COCOA_H_