Add a blocking version of the sync promo dialog

chrome/browser/ui/browser_dialogs.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_BROWSER_DIALOGS_H_
 #define CHROME_BROWSER_UI_BROWSER_DIALOGS_H_
 #pragma once
 
 #include "chrome/browser/ui/dialog_style.h"
 #include "ipc/ipc_message.h"
@@ skipping 31 matching lines @@
 // Returns the created window.
 //
 // Make sure to use the returned window only when you know it is safe
 // to do so, i.e. before OnDialogClosed() is called on the delegate.
 gfx::NativeWindow ShowHtmlDialog(gfx::NativeWindow parent,
                                  Profile* profile,
                                  Browser* browser,
                                  HtmlDialogUIDelegate* delegate,
                                  DialogStyle style);
 
+// Closes the given dialog.
+void CloseHtmlDialog(gfx::NativeWindow window);
+
 // Creates the ExtensionInstalledBubble and schedules it to be shown once
 // the extension has loaded. |extension| is the installed extension. |browser|
 // is the browser window which will host the bubble. |icon| is the install
 // icon of the extension.
 void ShowExtensionInstalledBubble(const Extension* extension,
                                   Browser* browser,
                                   const SkBitmap& icon,
                                   Profile* profile);
 
 // Shows or hide the hung renderer dialog for the given WebContents.
@@ skipping 10 matching lines @@
 void ConfirmAddSearchProvider(const TemplateURL* template_url,
                               Profile* profile);
 
 // Shows a tab-modal dialog box.
 void ShowTabModalConfirmDialog(TabModalConfirmDialogDelegate* delegate,
                                TabContentsWrapper* wrapper);
 
 }  // namespace browser
 
 #endif  // CHROME_BROWSER_UI_BROWSER_DIALOGS_H_