Don't retain NPNVWindowNPObject and NPNVPluginElementNPObject twice

webkit/plugins/npapi/webplugin.h

Index: webkit/plugins/npapi/webplugin.h
diff --git a/webkit/plugins/npapi/webplugin.h b/webkit/plugins/npapi/webplugin.h
index db3b98a01aec825e6228482b48d1a8e5fa8aee24..d6689cc087d5c84df91e6ce343206a67d3427198 100644
--- a/webkit/plugins/npapi/webplugin.h
+++ b/webkit/plugins/npapi/webplugin.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -92,10 +92,12 @@ class WebPlugin {
   virtual void Invalidate() = 0;
   virtual void InvalidateRect(const gfx::Rect& rect) = 0;
 
-  // Returns the NPObject for the browser's window object.
+  // Returns the NPObject for the browser's window object. Does not
+  // take a reference.
   virtual NPObject* GetWindowScriptNPObject() = 0;
 
-  // Returns the DOM element that loaded the plugin.
+  // Returns the DOM element that loaded the plugin. Does not take a
+  // reference.
   virtual NPObject* GetPluginElement() = 0;
 
   // Cookies