Support using TrackedCallbacks as hints to determine the handling thread of resource reply messages

ppapi/proxy/plugin_resource.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 "ppapi/proxy/plugin_resource.h"
 
 #include <limits>
 
+#include "ppapi/proxy/plugin_globals.h"
 #include "ppapi/proxy/ppapi_messages.h"
+#include "ppapi/shared_impl/ppapi_globals.h"
 
 namespace ppapi {
 namespace proxy {
 
 PluginResource::PluginResource(Connection connection, PP_Instance instance)
     : Resource(OBJECT_IS_PROXY, instance),
       connection_(connection),
       next_sequence_number_(1),
       sent_create_to_browser_(false),
-      sent_create_to_renderer_(false) {
+      sent_create_to_renderer_(false),
+      resource_reply_thread_registrar_(
+          PpapiGlobals::Get()->IsPluginGlobals() ?
+              PluginGlobals::Get()->resource_reply_thread_registrar() : NULL) {
 }
 
 PluginResource::~PluginResource() {
   if (sent_create_to_browser_) {
     connection_.browser_sender->Send(
         new PpapiHostMsg_ResourceDestroyed(pp_resource()));
   }
   if (sent_create_to_renderer_) {
     connection_.renderer_sender->Send(
         new PpapiHostMsg_ResourceDestroyed(pp_resource()));
   }
+
+  if (resource_reply_thread_registrar_)
+    resource_reply_thread_registrar_->Unregister(pp_resource());
 }
 
 void PluginResource::OnReplyReceived(
     const proxy::ResourceMessageReplyParams& params,
     const IPC::Message& msg) {
   TRACE_EVENT2("ppapi proxy", "PluginResource::OnReplyReceived",
                "Class", IPC_MESSAGE_ID_CLASS(msg.type()),
                "Line", IPC_MESSAGE_ID_LINE(msg.type()));
   // Grab the callback for the reply sequence number and run it with |msg|.
   CallbackMap::iterator it = callbacks_.find(params.sequence());
@@ skipping 110 matching lines @@
   int32_t ret = next_sequence_number_;
   if (next_sequence_number_ == std::numeric_limits<int32_t>::max())
     next_sequence_number_ = 1;  // Skip 0 which is invalid.
   else
     next_sequence_number_++;
   return ret;
 }
 
 }  // namespace proxy
 }  // namespace ppapi