RefCounted types should not have public destructors, content/browser part 2

content/renderer/plugin_channel_host.cc

Index: content/renderer/plugin_channel_host.cc
diff --git a/content/renderer/plugin_channel_host.cc b/content/renderer/plugin_channel_host.cc
index e0558528c8e2de8b7ff1e94fd63280646c35d2f1..f9f384eac9a117cf02fc8f8062b0671415764808 100644
--- a/content/renderer/plugin_channel_host.cc
+++ b/content/renderer/plugin_channel_host.cc
@@ -1,4 +1,4 @@
-// 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.
 
@@ -29,6 +29,9 @@ class IsListeningFilter : public IPC::ChannelProxy::MessageFilter {
 
   static bool is_listening_;
 
+ protected:
+  virtual ~IsListeningFilter() {}
+
  private:
   IPC::Channel* channel_;