Implement window open disposition for (some) navigation buttons....

chrome/browser/gtk/back_forward_button_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_BACK_FORWARD_BUTTON_GTK_
 #define CHROME_BROWSER_GTK_BACK_FORWARD_BUTTON_GTK_
 
 #include "base/scoped_ptr.h"
 #include "base/task.h"
 #include "chrome/browser/gtk/custom_button.h"
@@ skipping 18 matching lines @@
 
  private:
   // Executes the browser command.
   static void OnClick(GtkWidget* widget, BackForwardButtonGtk* button);
 
   // Starts a timer to show the dropdown menu.
   static gboolean OnButtonPress(GtkWidget* button,
                                 GdkEventButton* event,
                                 BackForwardButtonGtk* toolbar);
 
+  static gboolean OnButtonRelease(GtkWidget* button,
+                                  GdkEventButton* event,
+                                  BackForwardButtonGtk* toolbar);
+
   // If there is a timer to show the dropdown menu, and the mouse has moved
   // sufficiently down the screen, cancel the timer and immediately show the
   // menu.
   static gboolean OnMouseMove(GtkWidget* widget,
                               GdkEventMotion* event,
                               BackForwardButtonGtk* toolbar);
 
   // Shows the dropdown menu.
   void ShowBackForwardMenu();
 
   // The menu gets reset every time it is shown.
   scoped_ptr<MenuGtk> menu_;
 
   scoped_ptr<CustomDrawButton> button_;
 
   // The browser to which we will send commands.
   Browser* browser_;
 
   // Whether this button is a forward button.
   bool is_forward_;
 
+  // The event state from the last button release.
+  int last_release_event_flags_;
+
   // The dropdown menu delegate.
   scoped_ptr<BackForwardMenuModelGtk> menu_model_;
 
   // The y position of the last mouse down event.
   int y_position_of_last_press_;
 
   ScopedRunnableMethodFactory<BackForwardButtonGtk> show_menu_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(BackForwardButtonGtk);
 };
 
 #endif  // CHROME_BROWSER_GTK_BACK_FORWARD_BUTTON_GTK_