Gtk3 ui: Add libgtk3ui as a separate build component

chrome/browser/ui/libgtkui/app_indicator_icon.h

 // Copyright 2013 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_APP_INDICATOR_ICON_H_
-#define CHROME_BROWSER_UI_LIBGTK2UI_APP_INDICATOR_ICON_H_
+#ifndef CHROME_BROWSER_UI_LIBGTKUI_APP_INDICATOR_ICON_H_
+#define CHROME_BROWSER_UI_LIBGTKUI_APP_INDICATOR_ICON_H_
 
 #include <memory>
 
 #include "base/files/file_path.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/nix/xdg_util.h"
-#include "chrome/browser/ui/libgtk2ui/gtk2_signal.h"
+#include "chrome/browser/ui/libgtkui/gtk2_signal.h"
 #include "ui/views/linux_ui/status_icon_linux.h"
 
 typedef struct _AppIndicator AppIndicator;
 typedef struct _GtkWidget GtkWidget;
 
 class SkBitmap;
 
 namespace gfx {
 class ImageSkia;
 }
 
 namespace ui {
 class MenuModel;
 }
 
-namespace libgtk2ui {
+namespace libgtkui {
 class AppIndicatorIconMenu;
 
 // Status icon implementation which uses libappindicator.
 class AppIndicatorIcon : public views::StatusIconLinux {
  public:
   // The id uniquely identifies the new status icon from other chrome status
   // icons.
   AppIndicatorIcon(std::string id,
                    const gfx::ImageSkia& image,
                    const base::string16& tool_tip);
@@ skipping 57 matching lines @@
   ui::MenuModel* menu_model_;
 
   base::FilePath temp_dir_;
   int icon_change_count_;
 
   base::WeakPtrFactory<AppIndicatorIcon> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AppIndicatorIcon);
 };
 
-}  // namespace libgtk2ui
+}  // namespace libgtkui
 
-#endif  // CHROME_BROWSER_UI_LIBGTK2UI_APP_INDICATOR_ICON_H_
+#endif  // CHROME_BROWSER_UI_LIBGTKUI_APP_INDICATOR_ICON_H_