Patch by Thatcher Ulrich <tulrich@google.com>....

webkit/glue/plugins/webplugin_delegate_impl.h

Index: webkit/glue/plugins/webplugin_delegate_impl.h
===================================================================
--- webkit/glue/plugins/webplugin_delegate_impl.h	(revision 3135)
+++ webkit/glue/plugins/webplugin_delegate_impl.h	(working copy)
@@ -41,7 +41,9 @@
                           WebPlugin* plugin,
                           bool load_manually);
   virtual void UpdateGeometry(const gfx::Rect& window_rect,
-                              const gfx::Rect& clip_rect, bool visible);
+                              const gfx::Rect& clip_rect,
+                              const std::vector<gfx::Rect>& cutout_rects,
+                              bool visible);
   virtual void Paint(HDC hdc, const gfx::Rect& rect);
   virtual void Print(HDC hdc);
   virtual void SetFocus();  // only called when windowless
@@ -93,6 +95,7 @@
   static void MoveWindow(HWND window,
                          const gfx::Rect& window_rect,
                          const gfx::Rect& clip_rect,
+                         const std::vector<gfx::Rect>& cutout_rects,
                          bool visible);
 
  private:
@@ -103,7 +106,9 @@
   //--------------------------
   // used for windowed plugins
   void WindowedUpdateGeometry(const gfx::Rect& window_rect,
-                              const gfx::Rect& clip_rect, bool visible);
+                              const gfx::Rect& clip_rect,
+                              const std::vector<gfx::Rect>& cutout_rects,
+                              bool visible);
   // Create the native window. 
   // Returns true if the window is created (or already exists).
   // Returns false if unable to create the window.
@@ -115,7 +120,9 @@
   // Reposition the native window to be in sync with the given geometry.
   // Returns true if the native window has moved or been clipped differently.
   bool WindowedReposition(const gfx::Rect& window_rect,
-                          const gfx::Rect& clip_rect, bool visible);
+                          const gfx::Rect& clip_rect,
+                          const std::vector<gfx::Rect>& cutout_rects,
+                          bool visible);
 
   // Tells the plugin about the current state of the window.
   // See NPAPI NPP_SetWindow for more information.
@@ -187,6 +194,7 @@
   NPWindow window_;
   gfx::Rect window_rect_;
   gfx::Rect clip_rect_;
+  std::vector<gfx::Rect> cutout_rects_;
   int quirks_;
 
   // We only move/size the plugin window once after its creation. The