Add the PP_Instance to resource object base.

ppapi/proxy/plugin_resource.cc

 // 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.
 
 #include "ppapi/proxy/plugin_resource.h"
 
 namespace pp {
 namespace proxy {
 
 PluginResource::PluginResource(const HostResource& resource)
-    : host_resource_(resource) {
+    : ResourceObjectBase(resource.instance()),
+      host_resource_(resource) {
 }
 
 PluginResource::~PluginResource() {
 }
 
 #define DEFINE_TYPE_GETTER(RESOURCE)                    \
   RESOURCE* PluginResource::As##RESOURCE() { return NULL; }
 FOR_ALL_PLUGIN_RESOURCES(DEFINE_TYPE_GETTER)
 #undef DEFINE_TYPE_GETTER
 
 PluginDispatcher* PluginResource::GetDispatcher() {
   PluginDispatcher* disp = PluginDispatcher::GetForInstance(instance());
   CHECK(disp);
   return disp;
 }
 
 }  // namespace proxy
 }  // namespace pp