chrome: Cleanup class/struct forward declarations

chrome/browser/ui/views/sync/one_click_signin_dialog_view.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_SYNC_ONE_CLICK_SIGNIN_DIALOG_VIEW_H_
 #define CHROME_BROWSER_UI_VIEWS_SYNC_ONE_CLICK_SIGNIN_DIALOG_VIEW_H_
 
 #include <memory>
 
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/strings/string16.h"
 #include "chrome/browser/ui/browser_window.h"
 #include "chrome/browser/ui/sync/one_click_signin_links_delegate.h"
 #include "ui/views/controls/button/button.h"
 #include "ui/views/controls/link_listener.h"
 #include "ui/views/window/dialog_delegate.h"
 
 namespace views {
-class GridLayout;
-class ImageButton;
-class LabelButton;
 class View;
 }
 
 // This class allows users to confirm sync signin in cases where signin is
 // untrusted.
 class OneClickSigninDialogView : public views::DialogDelegateView,
                                  public views::LinkListener {
  public:
   // Show the one-click signin dialog if not already showing. |start_sync| is
   // called to start sync.
@@ skipping 55 matching lines @@
   // Link to the Learn More details page
   views::Link* learn_more_link_;
 
   // The bubble, if we're showing one.
   static OneClickSigninDialogView* dialog_view_;
 
   DISALLOW_COPY_AND_ASSIGN(OneClickSigninDialogView);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_SYNC_ONE_CLICK_SIGNIN_DIALOG_VIEW_H_