Add initial GTK web accessibility framework (third attempt).

ui/gfx/gtk_preserve_window.cc

 // Copyright (c) 2012 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.
 
 #include "ui/gfx/gtk_preserve_window.h"
 
 #include <gdk/gdk.h>
 #include <gtk/gtk.h>
 
 #include "ui/base/gtk/gtk_compat.h"
 
 G_BEGIN_DECLS
 
 #define GTK_PRESERVE_WINDOW_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), \
                                             GTK_TYPE_PRESERVE_WINDOW, \
                                             GtkPreserveWindowPrivate))
 
 typedef struct _GtkPreserveWindowPrivate GtkPreserveWindowPrivate;
 
 struct _GtkPreserveWindowPrivate {
   // If true, don't create/destroy windows on realize/unrealize.
   gboolean preserve_window;
 
   // Whether or not we delegate the resize of the GdkWindow
   // to someone else.
   gboolean delegate_resize;
+
+  // Accessible factory and userdata.
+  AtkObject* (*accessible_factory)(void* userdata);
+  void* accessible_factory_userdata;
 };
 
 G_DEFINE_TYPE(GtkPreserveWindow, gtk_preserve_window, GTK_TYPE_FIXED)
 
 static void gtk_preserve_window_destroy(GtkObject* object);
 static void gtk_preserve_window_realize(GtkWidget* widget);
 static void gtk_preserve_window_unrealize(GtkWidget* widget);
 static void gtk_preserve_window_size_allocate(GtkWidget* widget,
                                               GtkAllocation* allocation);
+static AtkObject* gtk_preserve_window_get_accessible(GtkWidget* widget);
 
 static void gtk_preserve_window_class_init(GtkPreserveWindowClass *klass) {
   GtkWidgetClass* widget_class = reinterpret_cast<GtkWidgetClass*>(klass);
   widget_class->realize = gtk_preserve_window_realize;
   widget_class->unrealize = gtk_preserve_window_unrealize;
   widget_class->size_allocate = gtk_preserve_window_size_allocate;
+  widget_class->get_accessible = gtk_preserve_window_get_accessible;
 
   GtkObjectClass* object_class = reinterpret_cast<GtkObjectClass*>(klass);
   object_class->destroy = gtk_preserve_window_destroy;
 
   GObjectClass* gobject_class = G_OBJECT_CLASS(klass);
   g_type_class_add_private(gobject_class, sizeof(GtkPreserveWindowPrivate));
 }
 
 static void gtk_preserve_window_init(GtkPreserveWindow* widget) {
   GtkPreserveWindowPrivate* priv = GTK_PRESERVE_WINDOW_GET_PRIVATE(widget);
   priv->preserve_window = FALSE;
+  priv->accessible_factory = NULL;
+  priv->accessible_factory_userdata = NULL;
 
   // These widgets always have their own window.
   gtk_widget_set_has_window(GTK_WIDGET(widget), TRUE);
 }
 
 GtkWidget* gtk_preserve_window_new() {
   return GTK_WIDGET(g_object_new(GTK_TYPE_PRESERVE_WINDOW, NULL));
 }
 
 static void gtk_preserve_window_destroy(GtkObject* object) {
@@ skipping 164 matching lines @@
     children = children->next;
   }
 }
 
 void gtk_preserve_window_delegate_resize(GtkPreserveWindow* widget,
                                          gboolean delegate) {
   GtkPreserveWindowPrivate* priv = GTK_PRESERVE_WINDOW_GET_PRIVATE(widget);
   priv->delegate_resize = delegate;
 }
 
+void gtk_preserve_window_set_accessible_factory(
+    GtkPreserveWindow* widget,
+    AtkObject* (*factory)(void* userdata),
+    gpointer userdata) {
+  GtkPreserveWindowPrivate* priv = GTK_PRESERVE_WINDOW_GET_PRIVATE(widget);
+  priv->accessible_factory = factory;
+  priv->accessible_factory_userdata = userdata;
+}
+
+AtkObject* gtk_preserve_window_get_accessible(GtkWidget* widget) {
+  GtkPreserveWindowPrivate* priv = GTK_PRESERVE_WINDOW_GET_PRIVATE(widget);
+  if (priv->accessible_factory) {
+    return priv->accessible_factory(priv->accessible_factory_userdata);
+  } else {
+    return GTK_WIDGET_CLASS(gtk_preserve_window_parent_class)
+        ->get_accessible(widget);
+  }
+}
+
 G_END_DECLS