Polish the look of Linux extension shelf.

chrome/browser/gtk/extension_shelf_gtk.h

 // Copyright (c) 2009 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_GTK_EXTENSION_SHELF_GTK_H_
 #define CHROME_BROWSER_GTK_EXTENSION_SHELF_GTK_H_
 
 #include <gtk/gtk.h>
 
 #include <set>
 
 #include "base/scoped_ptr.h"
 #include "chrome/browser/extensions/extension_shelf_model.h"
+#include "chrome/common/notification_registrar.h"
 #include "chrome/common/owned_widget_gtk.h"
 
 class Browser;
 class BrowserWindowGtk;
 class CustomContainerButton;
 class NineBox;
 class Profile;
 struct GtkThemeProvider;
 
-class ExtensionShelfGtk : public ExtensionShelfModelObserver {
+class ExtensionShelfGtk : public ExtensionShelfModelObserver,
+                          public NotificationObserver {
  public:
   ExtensionShelfGtk(Profile* profile, Browser* browser);
   virtual ~ExtensionShelfGtk();
 
   // Adds this GTK shelf into a sizing box.
   void AddShelfToBox(GtkWidget* box);
 
   // Change the visibility of the bookmarks bar. (Starts out hidden, per GTK's
   // default behaviour).
   void Show();
   void Hide();
 
   // ExtensionShelfModelObserver
   virtual void ToolstripInsertedAt(ExtensionHost* host, int index);
   virtual void ToolstripRemovingAt(ExtensionHost* host, int index);
   virtual void ToolstripMoved(ExtensionHost* host,
                               int from_index,
                               int to_index);
   virtual void ToolstripChanged(ExtensionShelfModel::iterator toolstrip);
   virtual void ExtensionShelfEmpty();
   virtual void ShelfModelReloaded();
   virtual void ShelfModelDeleting();
 
+  // NotificationObserver
+  virtual void Observe(NotificationType type,
+                       const NotificationSource& source,
+                       const NotificationDetails& details);
+
  private:
   class Toolstrip;
 
   // Create the contents of the extension shelf.
   void Init(Profile* profile);
 
   // Determines what is our target height and sets it.
   void AdjustHeight();
 
   void LoadFromModel();
 
   Toolstrip* ToolstripAtIndex(int index);
 
   // GtkHBox callbacks.
   static gboolean OnHBoxExpose(GtkWidget* widget, GdkEventExpose* event,
                                ExtensionShelfGtk* window);
 
   Browser* browser_;
 
+  // Top level event box which draws the one pixel border.
+  GtkWidget* top_border_;
+
   // Contains |shelf_hbox_|. Event box exists to prevent leakage of
   // background color from the toplevel application window's GDK window.
   OwnedWidgetGtk event_box_;
 
   // Used to position all children.
   GtkWidget* shelf_hbox_;
 
   GtkThemeProvider* theme_provider_;
 
   // The model representing the toolstrips on the shelf.
   ExtensionShelfModel* model_;
 
   // Set of toolstrip views which are really on the shelf.
   std::set<Toolstrip*> toolstrips_;
 
+  NotificationRegistrar registrar_;
+
   DISALLOW_COPY_AND_ASSIGN(ExtensionShelfGtk);
 };
 
 #endif  // CHROME_BROWSER_EXTENSION_SHELF_GTK_H_