(not for review) Fix composited-to-non-composited corruption on Linux.

content/browser/renderer_host/render_widget_host_view_gtk.h

 // 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.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_GTK_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_GTK_H_
 
 #include <gdk/gdk.h>
 
 #include <string>
@@ skipping 303 matching lines @@
   // monitor (if the widget is aligned with that edge). Negative values
   // indicate the left edge, positive the right.
   int dragged_at_horizontal_edge_;
 
   // The number of times the user has dragged against vertical edge  of the
   // monitor (if the widget is aligned with that edge). Negative values
   // indicate the top edge, positive the bottom.
   int dragged_at_vertical_edge_;
 
   gfx::PluginWindowHandle compositing_surface_;
+  bool last_frame_was_composited_;
 
   // The event for the last mouse down we handled. We need this for context
   // menus and drags.
   GdkEventButton* last_mouse_down_;
 
   // Instance of accessibility information for the root of the AtkObject
   // tree representation of the WebKit render tree.
   scoped_ptr<BrowserAccessibilityManager> browser_accessibility_manager_;
 
   ui::GtkSignalRegistrar signals_;
 
   ui::LatencyInfo software_latency_info_;
 };
 
 }  // namespace content
 
 #endif  // CHROME_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_GTK_H_