Begin work on extension shelf for Linux.

chrome/browser/gtk/extension_shelf_gtk.h

Index: chrome/browser/gtk/extension_shelf_gtk.h
diff --git a/chrome/browser/gtk/extension_shelf_gtk.h b/chrome/browser/gtk/extension_shelf_gtk.h
new file mode 100644
index 0000000000000000000000000000000000000000..849bc90fa239c6d12b18630db3a4442639ab1060
--- /dev/null
+++ b/chrome/browser/gtk/extension_shelf_gtk.h
@@ -0,0 +1,90 @@
+// 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 "base/scoped_ptr.h"
+#include "chrome/browser/extensions/extension_shelf_model.h"
+#include "chrome/common/notification_observer.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,
+                          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* toolstrip, int index);
+  virtual void ToolstripRemovingAt(ExtensionHost* toolstrip, int index);
+  virtual void ToolstripMoved(ExtensionHost* toolstrip,
+                              int from_index,
+                              int to_index);
+  virtual void ToolstripChangedAt(ExtensionHost* toolstrip, int index);
+  virtual void ExtensionShelfEmpty();
+  virtual void ShelfModelReloaded();
+
+ private:
+  // Create the contents of the extension shelf.
+  void Init(Profile* profile);
+
+  // Overridden from NotificationObserver:
+  virtual void Observe(NotificationType type,
+                       const NotificationSource& source,
+                       const NotificationDetails& details);
+
+  // Loads the background image into memory, or does nothing if already loaded.
+  void InitBackground();
+
+  // Determines what is our target height and sets it.
+  void AdjustHeight();
+
+  // GtkHBox callbacks.
+  static gboolean OnHBoxExpose(GtkWidget* widget, GdkEventExpose* event,
+                               ExtensionShelfGtk* window);
+
+  Browser* browser_;
+
+  // 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_;
+
+  // Label for placeholder text.
+  // TODO(phajdan.jr): Remove the placeholder label when we have real contents.
+  GtkWidget* label_;
+
+  GtkThemeProvider* theme_provider_;
+
+  // Paints the background for our bookmark bar.
+  scoped_ptr<NineBox> background_ninebox_;
+
+  NotificationRegistrar registrar_;
+
+  // The model representing the toolstrips on the shelf.
+  scoped_ptr<ExtensionShelfModel> model_;
+};
+
+#endif  // CHROME_BROWSER_EXTENSION_SHELF_GTK_H_