GTK: Seal up GSEALs, focusing on GtkSelectionData.

ui/gfx/screen_gtk.cc

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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/screen.h"
 
 #include <gdk/gdkx.h>
 #include <gtk/gtk.h>
 
 #include "base/logging.h"
 
@@ skipping 61 matching lines @@
 
 // static
 gfx::Rect Screen::GetMonitorAreaNearestWindow(gfx::NativeView view) {
   GdkScreen* screen = gdk_screen_get_default();
   gint monitor_num = 0;
   if (view) {
     GtkWidget* top_level = gtk_widget_get_toplevel(view);
     DCHECK(GTK_IS_WINDOW(top_level));
     GtkWindow* window = GTK_WINDOW(top_level);
     screen = gtk_window_get_screen(window);
-    monitor_num = gdk_screen_get_monitor_at_window(screen, top_level->window);
+    monitor_num = gdk_screen_get_monitor_at_window(
+        screen,
+        gtk_widget_get_window(top_level));
   }
   GdkRectangle bounds;
   gdk_screen_get_monitor_geometry(screen, monitor_num, &bounds);
   return gfx::Rect(bounds);
 }
 
 // static
 gfx::Rect Screen::GetMonitorWorkAreaNearestPoint(const gfx::Point& point) {
   // TODO(jamiewalch): Restrict this to the work area of the monitor.
   return GetMonitorAreaNearestPoint(point);
@@ skipping 55 matching lines @@
 
 // static
 int Screen::GetNumMonitors() {
   // This query is kinda bogus for Linux -- do we want number of X screens?
   // The number of monitors Xinerama has?  We'll just use whatever GDK uses.
   GdkScreen* screen = gdk_screen_get_default();
   return gdk_screen_get_n_monitors(screen);
 }
 
 }  // namespace gfx