Fix check for removed plug-in while loading a blocked plug-in.

chrome/renderer/plugins/plugin_placeholder.cc

 // 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 "chrome/renderer/plugins/plugin_placeholder.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/json/string_escape.h"
 #include "base/strings/string_piece.h"
@@ skipping 305 matching lines @@
   // initialization.
   WebElement element = container->element();
   if (!new_plugin->initialize(container)) {
     // We couldn't initialize the new plug-in. Restore the old one and abort.
     container->setPlugin(plugin_);
     return;
   }
 
   // The plug-in has been removed from the page. Destroy the old plug-in
   // (which will destroy us).
-  if (element.parentNode().isNull()) {
+  if (!element.pluginContainer()) {
     plugin_->destroy();
     return;
   }
 
   // During initialization, the new plug-in might have replaced itself in turn
   // with another plug-in. Make sure not to use the passed in |new_plugin| after
   // this point.
   new_plugin = container->plugin();
 
   plugin_->RestoreTitleText();
@@ skipping 280 matching lines @@
 bool PluginPlaceholder::IsYouTubeURL(const GURL& url,
                                        const std::string& mime_type) {
   std::string host = url.host();
   bool is_youtube = EndsWith(host, "youtube.com", true) ||
       EndsWith(host, "youtube-nocookie.com", true);
 
   return is_youtube && IsValidYouTubeVideo(url.path()) &&
       LowerCaseEqualsASCII(mime_type, content::kFlashPluginSwfMimeType);
 }
 #endif