Gtk3 ui: Add libgtk3ui as a separate build component

chrome/browser/ui/libgtk2ui/gtk2_status_icon.h

-// Copyright 2014 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_LIBGTK2UI_GTK2_STATUS_ICON_H_
-#define CHROME_BROWSER_UI_LIBGTK2UI_GTK2_STATUS_ICON_H_
-
-#include <memory>
-
-#include "base/macros.h"
-#include "base/strings/string16.h"
-#include "chrome/browser/ui/libgtk2ui/gtk2_signal.h"
-#include "ui/base/glib/glib_integers.h"
-#include "ui/base/glib/glib_signal.h"
-#include "ui/views/linux_ui/status_icon_linux.h"
-
-typedef struct _GtkStatusIcon GtkStatusIcon;
-
-namespace gfx {
-class ImageSkia;
-}
-
-namespace ui {
-class MenuModel;
-}
-
-namespace libgtk2ui {
-class AppIndicatorIconMenu;
-
-// Status icon implementation which uses the system tray X11 spec (via
-// GtkStatusIcon).
-class Gtk2StatusIcon : public views::StatusIconLinux {
- public:
-  Gtk2StatusIcon(const gfx::ImageSkia& image, const base::string16& tool_tip);
-  ~Gtk2StatusIcon() override;
-
-  // Overridden from views::StatusIconLinux:
-  void SetImage(const gfx::ImageSkia& image) override;
-  void SetToolTip(const base::string16& tool_tip) override;
-  void UpdatePlatformContextMenu(ui::MenuModel* menu) override;
-  void RefreshPlatformContextMenu() override;
-
- private:
-  CHROMEG_CALLBACK_0(Gtk2StatusIcon, void, OnClick, GtkStatusIcon*);
-
-  CHROMEG_CALLBACK_2(Gtk2StatusIcon,
-                     void,
-                     OnContextMenuRequested,
-                     GtkStatusIcon*,
-                     guint,
-                     guint);
-
-  GtkStatusIcon* gtk_status_icon_;
-
-  std::unique_ptr<AppIndicatorIconMenu> menu_;
-
-  DISALLOW_COPY_AND_ASSIGN(Gtk2StatusIcon);
-};
-
-}  // namespace libgtk2ui
-
-#endif  // CHROME_BROWSER_UI_LIBGTK2UI_GTK2_STATUS_ICON_H_