Reapply r50859 with chromeos fixes.

chrome/browser/gtk/gtk_custom_menu.cc

+// Copyright (c) 2010 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 "chrome/browser/gtk/gtk_custom_menu.h"
+
+#include "chrome/browser/gtk/gtk_custom_menu_item.h"
+
+G_DEFINE_TYPE(GtkCustomMenu, gtk_custom_menu, GTK_TYPE_MENU)
+
+// Stolen directly from gtkmenushell.c. I'd love to call the library version
+// instead, but it's static and isn't exported. :(
+static gint gtk_menu_shell_is_item(GtkMenuShell* menu_shell,
+                                   GtkWidget* child) {
+  GtkWidget *parent;
+
+  g_return_val_if_fail(GTK_IS_MENU_SHELL(menu_shell), FALSE);
+  g_return_val_if_fail(child != NULL, FALSE);
+
+  parent = child->parent;
+  while (GTK_IS_MENU_SHELL(parent)) {
+    if (parent == reinterpret_cast<GtkWidget*>(menu_shell))
+      return TRUE;
+    parent = GTK_MENU_SHELL(parent)->parent_menu_shell;
+  }
+
+  return FALSE;
+}
+
+// Stolen directly from gtkmenushell.c. I'd love to call the library version
+// instead, but it's static and isn't exported. :(
+static GtkWidget* gtk_menu_shell_get_item(GtkMenuShell* menu_shell,
+                                          GdkEvent* event) {
+  GtkWidget* menu_item = gtk_get_event_widget(event);
+
+  while (menu_item && !GTK_IS_MENU_ITEM(menu_item))
+    menu_item = menu_item->parent;
+
+  if (menu_item && gtk_menu_shell_is_item(menu_shell, menu_item))
+    return menu_item;
+  else
+    return NULL;
+}
+
+// When processing a button event, abort processing if the cursor isn't in a
+// clickable region.
+static gboolean gtk_custom_menu_button_press(GtkWidget* widget,
+                                             GdkEventButton* event) {
+  GtkWidget* menu_item = gtk_menu_shell_get_item(
+      GTK_MENU_SHELL(widget), reinterpret_cast<GdkEvent*>(event));
+  if (GTK_IS_CUSTOM_MENU_ITEM(menu_item)) {
+    if (!gtk_custom_menu_item_is_in_clickable_region(
+            GTK_CUSTOM_MENU_ITEM(menu_item))) {
+      return TRUE;
+    }
+  }
+
+  return GTK_WIDGET_CLASS(gtk_custom_menu_parent_class)->
+      button_press_event(widget, event);
+}
+
+// When processing a button event, abort processing if the cursor isn't in a
+// clickable region.
+static gboolean gtk_custom_menu_button_release(GtkWidget* widget,
+                                               GdkEventButton* event) {
+  GtkWidget* menu_item = gtk_menu_shell_get_item(
+      GTK_MENU_SHELL(widget), reinterpret_cast<GdkEvent*>(event));
+  if (GTK_IS_CUSTOM_MENU_ITEM(menu_item)) {
+    if (!gtk_custom_menu_item_is_in_clickable_region(
+            GTK_CUSTOM_MENU_ITEM(menu_item))) {
+      // Stop processing this event. This isn't a clickable region.
+      return TRUE;
+    }
+  }
+
+  return GTK_WIDGET_CLASS(gtk_custom_menu_parent_class)->
+      button_release_event(widget, event);
+}
+
+// Manually forward button press events to the menu item (and then do what we'd
+// do normally).
+static gboolean gtk_custom_menu_motion_notify(GtkWidget* widget,
+                                              GdkEventMotion* event) {
+  GtkWidget* menu_item = gtk_menu_shell_get_item(
+      GTK_MENU_SHELL(widget), (GdkEvent*)event);
+  if (GTK_IS_CUSTOM_MENU_ITEM(menu_item)) {
+    gtk_custom_menu_item_receive_motion_event(GTK_CUSTOM_MENU_ITEM(menu_item),
+                                              event->x, event->y);
+  }
+
+  return GTK_WIDGET_CLASS(gtk_custom_menu_parent_class)->
+      motion_notify_event(widget, event);
+}
+
+static void gtk_custom_menu_move_current(GtkMenuShell* menu_shell,
+                                         GtkMenuDirectionType direction) {
+  // If the currently selected item is custom, we give it first chance to catch
+  // up/down events.
+
+  // TODO(erg): We are breaking a GSEAL by directly accessing this. We'll need
+  // to fix this by the time gtk3 comes out.
+  GtkWidget* menu_item = GTK_MENU_SHELL(menu_shell)->active_menu_item;
+  if (GTK_IS_CUSTOM_MENU_ITEM(menu_item)) {
+    switch (direction) {
+      case GTK_MENU_DIR_PREV:
+      case GTK_MENU_DIR_NEXT:
+        if (gtk_custom_menu_item_handle_move(GTK_CUSTOM_MENU_ITEM(menu_item),
+                                             direction))
+          return;
+        break;
+      default:
+        break;
+    }
+  }
+
+  GTK_MENU_SHELL_CLASS(gtk_custom_menu_parent_class)->
+      move_current(menu_shell, direction);
+
+  // In the case of hitting PREV and transitioning to a custom menu, we want to
+  // make sure we're selecting the final item in the list, not the first one.
+  menu_item = GTK_MENU_SHELL(menu_shell)->active_menu_item;
+  if (GTK_IS_CUSTOM_MENU_ITEM(menu_item)) {
+    gtk_custom_menu_item_select_item_by_direction(
+        GTK_CUSTOM_MENU_ITEM(menu_item), direction);
+  }
+}
+
+static void gtk_custom_menu_init(GtkCustomMenu* menu) {
+}
+
+static void gtk_custom_menu_class_init(GtkCustomMenuClass* klass) {
+  GtkWidgetClass* widget_class = GTK_WIDGET_CLASS(klass);
+  GtkMenuShellClass* menu_shell_class = GTK_MENU_SHELL_CLASS(klass);
+
+  widget_class->button_press_event = gtk_custom_menu_button_press;
+  widget_class->button_release_event = gtk_custom_menu_button_release;
+  widget_class->motion_notify_event = gtk_custom_menu_motion_notify;
+
+  menu_shell_class->move_current = gtk_custom_menu_move_current;
+}
+
+GtkWidget* gtk_custom_menu_new() {
+  return GTK_WIDGET(g_object_new(GTK_TYPE_CUSTOM_MENU, NULL));
+}