Fix a crash related to PPAPI scripting.

ppapi/proxy/dispatcher.h

Index: ppapi/proxy/dispatcher.h
diff --git a/ppapi/proxy/dispatcher.h b/ppapi/proxy/dispatcher.h
index b0af8eafecac227f44e7780c4e629d0e0e4950b8..35a82ab792b464b0e5f3fccbe333401af1398be5 100644
--- a/ppapi/proxy/dispatcher.h
+++ b/ppapi/proxy/dispatcher.h
@@ -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.
 
@@ -10,6 +10,7 @@
 #include <vector>
 
 #include "base/callback_forward.h"
+#include "base/memory/ref_counted.h"
 #include "base/tracked_objects.h"
 #include "ipc/ipc_channel_proxy.h"
 #include "ppapi/c/pp_instance.h"
@@ -87,7 +88,7 @@ class PPAPI_PROXY_EXPORT Dispatcher : public ProxyChannel {
              GetInterfaceFunc local_get_interface);
 
   // Setter for the derived classes to set the appropriate var serialization.
-  // Takes ownership of the given pointer, which must be on the heap.
+  // Takes one reference of the given pointer, which must be on the heap.
   void SetSerializationRules(VarSerializationRules* var_serialization_rules);
 
   // Called when an invalid message is received from the remote site. The
@@ -109,7 +110,7 @@ class PPAPI_PROXY_EXPORT Dispatcher : public ProxyChannel {
 
   GetInterfaceFunc local_get_interface_;
 
-  scoped_ptr<VarSerializationRules> serialization_rules_;
+  scoped_refptr<VarSerializationRules> serialization_rules_;
 
   DISALLOW_COPY_AND_ASSIGN(Dispatcher);
 };