GTK: Move code shared by future content/ classes and chrome/ to ui/.

chrome/browser/ui/gtk/focus_store_gtk.h

-// Copyright (c) 2011 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_GTK_FOCUS_STORE_GTK_H_
-#define CHROME_BROWSER_UI_GTK_FOCUS_STORE_GTK_H_
-#pragma once
-
-#include "base/basictypes.h"
-
-typedef struct _GtkWidget GtkWidget;
-
-class FocusStoreGtk {
- public:
-  FocusStoreGtk();
-
-  virtual ~FocusStoreGtk();
-
-  GtkWidget* widget() const { return widget_; }
-
-  // Save the widget that is currently focused for |widget|'s toplevel (NOT
-  // |widget|).
-  void Store(GtkWidget* widget);
-
-  // Save |widget| as the focus widget. Call with NULL to clear |widget_|.
-  void SetWidget(GtkWidget* widget);
-
- private:
-  // Disconnect the previous destroy handler (if any).
-  void DisconnectDestroyHandler();
-
-  // The widget which last had focus.
-  GtkWidget* widget_;
-
-  // The widget for which we've stored focus might be destroyed by the time we
-  // want to restore focus. Thus we connect to the "destroy" signal on that
-  // widget. This is the ID for the destroy handler.
-  unsigned int destroy_handler_id_;
-
-  DISALLOW_COPY_AND_ASSIGN(FocusStoreGtk);
-};
-
-#endif  // CHROME_BROWSER_UI_GTK_FOCUS_STORE_GTK_H_