Fix a crash related to PPAPI scripting.

ppapi/proxy/dispatcher.cc

Index: ppapi/proxy/dispatcher.cc
diff --git a/ppapi/proxy/dispatcher.cc b/ppapi/proxy/dispatcher.cc
index 8ba7830b1160a57834e3df948e23c2adc7533004..a2a1d7137a38f2caf5f180d28abe2a795cca3eaf 100644
--- a/ppapi/proxy/dispatcher.cc
+++ b/ppapi/proxy/dispatcher.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.
 
@@ -70,7 +70,7 @@ bool Dispatcher::OnMessageReceived(const IPC::Message& msg) {
 
 void Dispatcher::SetSerializationRules(
     VarSerializationRules* var_serialization_rules) {
-  serialization_rules_.reset(var_serialization_rules);
+  serialization_rules_ = var_serialization_rules;
 }
 
 void Dispatcher::OnInvalidMessageReceived() {